feat(insights): GLP1 therapy timeline on /insights/medikamente

Phase 8 of W4d GLP-1 full integration. New TherapyTimeline component
mounts on /insights/medikamente below the compliance grid. Renders a
chronological merge of every GLP-1-relevant event the user has logged:
dose changes (with up/down arrow against the previous step),
injections (with optional site), inventory events, and side-effect
days collapsed from MoodEntry tags.

Self-hides for users without a GLP-1 medication (the API returns
`hasGlp1: false`), so /insights/medikamente keeps its v1.4.24 look
for everyone else.

New GET /api/insights/glp1-timeline aggregates the data. Caps at 60
entries by default (configurable to 200 via ?limit) to keep the list
readable; older events surface via the existing intake-history page.

DE + EN copy for the surface lives under insights.therapyTimeline.
The medikamente sub-page description gains a one-liner explaining
when the timeline appears.

messages/de.json

@@ -560,6 +560,15 @@
     "siteThighRight": "Rechter Oberschenkel",
     "siteUpperArmLeft": "Linker Oberarm",
     "siteUpperArmRight": "Rechter Oberarm",
+    "sideEffectTagsLabel": "Häufige GLP-1-Nebenwirkungen",
+    "sideEffectTagsHelp": "Tippe einen Chip, um ihn zu den Mood-Tags hinzuzufügen.",
+    "sideEffectTagNausea": "Übelkeit",
+    "sideEffectTagConstipation": "Verstopfung",
+    "sideEffectTagDiarrhea": "Durchfall",
+    "sideEffectTagFatigue": "Müdigkeit",
+    "sideEffectTagAppetiteLoss": "Appetitlosigkeit",
+    "sideEffectTagHeartburn": "Sodbrennen",
+    "sideEffectTagHeadache": "Kopfschmerzen",
     "newSchedule": "Neues Zeitfenster",
     "removeSchedule": "Zeitfenster entfernen",
     "advancedEditing": "Erweiterte Bearbeitung",
@@ -879,6 +888,14 @@
       "emptyAction": "Briefing erstellen",
       "loadingLabel": "Briefing wird zusammengestellt"
     },
+    "therapyTimeline": {
+      "title": "GLP-1-Therapieverlauf",
+      "description": "Chronologische Liste: Dosis-Änderungen, Injektionen, Bestand und Nebenwirkungstage.",
+      "empty": "Keine GLP-1-Ereignisse in den letzten 90 Tagen.",
+      "doseTo": "Dosis auf",
+      "pens": "Pens",
+      "sideEffects": "Nebenwirkungen"
+    },
     "trendsRow": {
       "title": "Trends",
       "subtitle": "Die letzten 30 Tage auf einen Blick"

messages/en.json

@@ -560,6 +560,15 @@
     "siteThighRight": "Right thigh",
     "siteUpperArmLeft": "Left upper arm",
     "siteUpperArmRight": "Right upper arm",
+    "sideEffectTagsLabel": "Common GLP-1 side effects",
+    "sideEffectTagsHelp": "Tap a chip to add it to your mood-entry tags.",
+    "sideEffectTagNausea": "nausea",
+    "sideEffectTagConstipation": "constipation",
+    "sideEffectTagDiarrhea": "diarrhea",
+    "sideEffectTagFatigue": "fatigue",
+    "sideEffectTagAppetiteLoss": "appetite-loss",
+    "sideEffectTagHeartburn": "heartburn",
+    "sideEffectTagHeadache": "headache",
     "newSchedule": "New schedule",
     "removeSchedule": "Remove schedule",
     "advancedEditing": "Advanced editing",
@@ -879,6 +888,14 @@
       "emptyAction": "Generate briefing",
       "loadingLabel": "Synthesising today's briefing"
     },
+    "therapyTimeline": {
+      "title": "GLP-1 therapy timeline",
+      "description": "Chronological log of dose changes, injections, inventory events, and side-effect days.",
+      "empty": "No GLP-1 therapy events logged in the last 90 days.",
+      "doseTo": "dose set to",
+      "pens": "pens",
+      "sideEffects": "Side effects"
+    },
     "trendsRow": {
       "title": "Trends",
       "subtitle": "Last 30 days at a glance"
@@ -1016,6 +1033,7 @@
       "medikamenteEmptyTitle": "Add your first medication",
       "medikamenteEmptyDescription": "Compliance insights need at least one tracked medication.",
       "medikamenteEmptyAction": "Open medications",
+      "therapyTimelineDescription": "Chronological GLP-1 therapy log — dose changes, injections, inventory, side effects.",
       "bmiDescription": "BMI derived from your weight and height, with a written AI assessment."
     },
     "sleep": {

src/app/api/insights/glp1-timeline/route.ts

@@ -0,0 +1,169 @@
+/**
+ * v1.4.25 W4d — GLP-1 therapy-timeline aggregator.
+ *
+ * Returns a chronological merge of every GLP-1-relevant event the user
+ * has logged: dose changes, injections (with site if recorded),
+ * inventory events, and side-effect-tagged mood entries from the
+ * trailing 90 days. Used by /insights/medikamente's TherapyTimeline
+ * component. Web-only users without a GLP-1 medication get
+ * `hasGlp1: false` so the component hides cleanly.
+ */
+
+import { prisma } from "@/lib/db";
+import { apiHandler, requireAuth } from "@/lib/api-handler";
+import { apiSuccess } from "@/lib/api-response";
+import { NextRequest } from "next/server";
+
+const DEFAULT_LIMIT = 60;
+const SIDE_EFFECT_TAGS = new Set([
+  "nausea",
+  "constipation",
+  "diarrhea",
+  "fatigue",
+  "appetite-loss",
+  "heartburn",
+  "headache",
+  "übelkeit",
+  "verstopfung",
+  "durchfall",
+  "müdigkeit",
+  "appetitlosigkeit",
+  "sodbrennen",
+  "kopfschmerzen",
+]);
+
+interface TimelineEntry {
+  date: string;
+  kind: "dose-change" | "injection" | "inventory" | "side-effect";
+  medicationName?: string;
+  doseValue?: number;
+  doseUnit?: string;
+  doseDelta?: "up" | "down" | null;
+  note?: string | null;
+  injectionSite?: string | null;
+  inventoryDelta?: number;
+  reason?: string;
+  tags?: string[];
+}
+
+function parseTagList(raw: string | null): string[] {
+  if (!raw) return [];
+  try {
+    const parsed = JSON.parse(raw);
+    if (Array.isArray(parsed)) {
+      return parsed
+        .map((v) => (typeof v === "string" ? v.trim() : ""))
+        .filter(Boolean);
+    }
+  } catch {
+    /* fall through */
+  }
+  return raw
+    .split(",")
+    .map((p) => p.trim())
+    .filter(Boolean);
+}
+
+export const GET = apiHandler(async (request: NextRequest) => {
+  const { user } = await requireAuth();
+  const url = new URL(request.url);
+  const rawLimit = Number(url.searchParams.get("limit"));
+  const limit =
+    Number.isInteger(rawLimit) && rawLimit > 0 && rawLimit <= 200
+      ? rawLimit
+      : DEFAULT_LIMIT;
+
+  const meds = await prisma.medication.findMany({
+    where: { userId: user.id, treatmentClass: "GLP1" },
+    include: {
+      doseChanges: { orderBy: { effectiveFrom: "asc" } },
+      intakeEvents: {
+        where: { takenAt: { not: null } },
+        orderBy: { takenAt: "desc" },
+        take: 50,
+      },
+      inventoryEvents: { orderBy: { occurredAt: "desc" }, take: 20 },
+    },
+  });
+
+  if (meds.length === 0) {
+    return apiSuccess({ hasGlp1: false, entries: [] });
+  }
+
+  const ninetyDaysAgo = new Date();
+  ninetyDaysAgo.setDate(ninetyDaysAgo.getDate() - 90);
+  const moods = await prisma.moodEntry.findMany({
+    where: { userId: user.id, moodLoggedAt: { gte: ninetyDaysAgo } },
+    select: { moodLoggedAt: true, tags: true },
+    orderBy: { moodLoggedAt: "desc" },
+  });
+
+  const entries: TimelineEntry[] = [];
+
+  for (const med of meds) {
+    const sortedChanges = [...med.doseChanges];
+    for (let i = 0; i < sortedChanges.length; i += 1) {
+      const dc = sortedChanges[i];
+      const prev = i > 0 ? sortedChanges[i - 1] : null;
+      let delta: "up" | "down" | null = null;
+      if (prev) {
+        if (dc.doseValue > prev.doseValue) delta = "up";
+        else if (dc.doseValue < prev.doseValue) delta = "down";
+      }
+      entries.push({
+        date: dc.effectiveFrom.toISOString(),
+        kind: "dose-change",
+        medicationName: med.name,
+        doseValue: dc.doseValue,
+        doseUnit: dc.doseUnit,
+        doseDelta: delta,
+        note: dc.note,
+      });
+    }
+    for (const intake of med.intakeEvents) {
+      if (!intake.takenAt) continue;
+      entries.push({
+        date: intake.takenAt.toISOString(),
+        kind: "injection",
+        medicationName: med.name,
+        injectionSite: intake.injectionSite,
+      });
+    }
+    for (const inv of med.inventoryEvents) {
+      entries.push({
+        date: inv.occurredAt.toISOString(),
+        kind: "inventory",
+        medicationName: med.name,
+        inventoryDelta: inv.delta,
+        reason: inv.reason,
+      });
+    }
+  }
+
+  // Side-effect days — collapse to one entry per day (most recent
+  // first) listing every recognised tag picked up that day.
+  const sideEffectByDay = new Map<string, string[]>();
+  for (const mood of moods) {
+    const tags = parseTagList(mood.tags).filter((t) =>
+      SIDE_EFFECT_TAGS.has(t.toLowerCase()),
+    );
+    if (tags.length === 0) continue;
+    const dayKey = mood.moodLoggedAt.toISOString().slice(0, 10);
+    const existing = sideEffectByDay.get(dayKey) ?? [];
+    for (const t of tags) {
+      if (!existing.includes(t)) existing.push(t);
+    }
+    sideEffectByDay.set(dayKey, existing);
+  }
+  for (const [day, tags] of sideEffectByDay) {
+    entries.push({
+      date: `${day}T12:00:00Z`,
+      kind: "side-effect",
+      tags,
+    });
+  }
+
+  entries.sort((a, b) => b.date.localeCompare(a.date));
+
+  return apiSuccess({ hasGlp1: true, entries: entries.slice(0, limit) });
+});

src/app/insights/medikamente/page.tsx

@@ -14,6 +14,7 @@ import { Progress } from "@/components/ui/progress";
 import { ComplianceHeatmap } from "@/components/charts/compliance-heatmap";
 import { InsightStatusCard } from "@/components/insights/insight-status-card";
 import { SubPageShell } from "@/components/insights/sub-page-shell";
+import { TherapyTimeline } from "@/components/insights/therapy-timeline";
 
 /**
  * v1.4.25 W4 — `/insights/medikamente`.
@@ -214,6 +215,11 @@ export default function InsightsMedikamentePage() {
         updatedAt={status?.updatedAt ?? null}
         loading={isStatusLoading}
       />
+
+      {/* v1.4.25 W4d — GLP-1 therapy timeline. Self-hides for users
+          without an active GLP-1 medication, so the page collapses
+          back to the compliance grid for everyone else. */}
+      <TherapyTimeline />
     </SubPageShell>
   );
 }

src/components/insights/therapy-timeline.tsx

@@ -0,0 +1,185 @@
+"use client";
+
+import { useQuery } from "@tanstack/react-query";
+import { ArrowDown, ArrowUp, Pill, Syringe } from "lucide-react";
+
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+import { useTranslations, useFormatters } from "@/lib/i18n/context";
+import { describeInjectionSite, type InjectionSiteKey } from "@/lib/medications/injection-sites";
+
+/**
+ * v1.4.25 W4d — therapy-timeline view for /insights/medikamente.
+ *
+ * Renders a chronological list of GLP-1 therapy events: dose changes,
+ * injections (with site if recorded), inventory events, side-effect tag
+ * occurrences. Pure list view — no chart — so the medications-page
+ * "no chart on the medication card" rule stays consistent across all
+ * GLP-1 surfaces; the dose curve lives on the Dashboard tile only.
+ *
+ * Self-hides for users with no GLP-1 medications (the parent route does
+ * the gating via a non-200 from the API endpoint).
+ */
+
+interface TimelineEntry {
+  date: string;
+  kind: "dose-change" | "injection" | "inventory" | "side-effect";
+  medicationName?: string;
+  doseValue?: number;
+  doseUnit?: string;
+  doseDelta?: "up" | "down" | null;
+  note?: string | null;
+  injectionSite?: InjectionSiteKey | null;
+  inventoryDelta?: number;
+  reason?: string;
+  tags?: string[];
+}
+
+interface TherapyTimelineResponse {
+  hasGlp1: boolean;
+  entries: TimelineEntry[];
+}
+
+interface TherapyTimelineProps {
+  /** Optional cap — defaults to the API's default (60 entries). */
+  limit?: number;
+}
+
+export function TherapyTimeline({ limit }: TherapyTimelineProps) {
+  const { t } = useTranslations();
+  const fmt = useFormatters();
+
+  const { data, isLoading } = useQuery({
+    queryKey: ["insights", "glp1-timeline", limit ?? "default"],
+    queryFn: async () => {
+      const url = limit
+        ? `/api/insights/glp1-timeline?limit=${limit}`
+        : "/api/insights/glp1-timeline";
+      const res = await fetch(url);
+      if (!res.ok) return null;
+      const json = await res.json();
+      return json.data as TherapyTimelineResponse;
+    },
+    staleTime: 60 * 1000,
+  });
+
+  if (isLoading || !data || !data.hasGlp1) return null;
+  if (data.entries.length === 0) {
+    return (
+      <Card data-slot="therapy-timeline">
+        <CardHeader className="pb-2">
+          <CardTitle className="flex items-center gap-2 text-base">
+            <Syringe className="text-dracula-purple h-4 w-4" />
+            {t("insights.therapyTimeline.title")}
+          </CardTitle>
+        </CardHeader>
+        <CardContent>
+          <p className="text-muted-foreground text-sm">
+            {t("insights.therapyTimeline.empty")}
+          </p>
+        </CardContent>
+      </Card>
+    );
+  }
+
+  return (
+    <Card data-slot="therapy-timeline">
+      <CardHeader className="pb-2">
+        <CardTitle className="flex items-center gap-2 text-base">
+          <Syringe className="text-dracula-purple h-4 w-4" />
+          {t("insights.therapyTimeline.title")}
+        </CardTitle>
+        <p className="text-muted-foreground text-xs">
+          {t("insights.therapyTimeline.description")}
+        </p>
+      </CardHeader>
+      <CardContent>
+        <ol className="border-border/60 relative space-y-3 border-l pl-4">
+          {data.entries.map((entry, idx) => (
+            <li key={idx} className="relative">
+              <span
+                className="border-background absolute top-1 -left-[18px] h-3 w-3 rounded-full border-2"
+                aria-hidden="true"
+                style={{ backgroundColor: colourForKind(entry.kind) }}
+              />
+              <div className="space-y-0.5">
+                <p className="text-muted-foreground text-xs">
+                  {fmt.dateWithWeekday(new Date(entry.date))}
+                </p>
+                <p className="text-foreground/90 text-sm">
+                  {renderEntryLine(entry, t)}
+                </p>
+                {entry.note && (
+                  <p className="text-muted-foreground text-xs italic">
+                    {entry.note}
+                  </p>
+                )}
+              </div>
+            </li>
+          ))}
+        </ol>
+      </CardContent>
+    </Card>
+  );
+}
+
+function colourForKind(kind: TimelineEntry["kind"]): string {
+  switch (kind) {
+    case "dose-change":
+      return "var(--dracula-purple)";
+    case "injection":
+      return "var(--dracula-cyan)";
+    case "inventory":
+      return "var(--dracula-yellow)";
+    case "side-effect":
+      return "var(--dracula-orange)";
+  }
+}
+
+function renderEntryLine(
+  entry: TimelineEntry,
+  t: (key: string, params?: Record<string, string | number>) => string,
+): React.ReactNode {
+  const drug = entry.medicationName ?? "";
+  switch (entry.kind) {
+    case "dose-change": {
+      const arrow = entry.doseDelta === "up" ? <ArrowUp className="inline h-3 w-3" /> : entry.doseDelta === "down" ? <ArrowDown className="inline h-3 w-3" /> : null;
+      return (
+        <span>
+          <strong>{drug}</strong> {t("insights.therapyTimeline.doseTo")}{" "}
+          <span className="tabular-nums font-medium">
+            {entry.doseValue} {entry.doseUnit}
+          </span>
+          {arrow && <> {arrow}</>}
+        </span>
+      );
+    }
+    case "injection": {
+      const site = entry.injectionSite
+        ? ` · ${t(describeInjectionSite(entry.injectionSite))}`
+        : "";
+      return (
+        <span>
+          <Pill className="text-dracula-cyan mr-1 inline h-3 w-3" />
+          <strong>{drug}</strong>
+          {site}
+        </span>
+      );
+    }
+    case "inventory": {
+      const sign = entry.inventoryDelta && entry.inventoryDelta > 0 ? "+" : "";
+      return (
+        <span>
+          <strong>{drug}</strong> · {sign}
+          {entry.inventoryDelta} {t("insights.therapyTimeline.pens")} ({entry.reason})
+        </span>
+      );
+    }
+    case "side-effect": {
+      return (
+        <span>
+          {t("insights.therapyTimeline.sideEffects")}: {(entry.tags ?? []).join(", ")}
+        </span>
+      );
+    }
+  }
+}