refactor(targets): extract TargetCard + RangeBar + ConsistencyStrip + TargetCoachButton

The /targets page composed everything inline in a 790-line page.tsx.
Break it into focused primitives under src/components/targets/ so the
W3e redesign can iterate per-card without growing the page file:

- target-card.tsx — the redesigned card composition. Headline + verbal
  status pill, big-number row with inline trend chevron, range bar,
  consistency strip, recency + streak chips (both conditional on real
  data), per-card Coach CTA gated by aiEnabled, source link footer.
  MOOD_STABILITY swaps the raw σ headline for a verbal label via the
  moodStabilityLabel helper. Fixed card order is owned by the page;
  this component is presentational.
- range-bar.tsx — extracted intact from page.tsx. Same behaviour, same
  data-slot. Now carries its own test suite.
- consistency-strip.tsx — NEW. 7 dots (one per Berlin-tz day), each
  filled / amber / red / hollow per the day's band classification.
  Caption flips between "X of 7 in range" and "X of 7 logged" when
  cadence is the more informative signal. Accessible: <ul role="list">
  with per-dot aria-labels seeded from i18n. No empty-state copy
  inside the strip — Marc directive: hide entirely when insufficient.
- target-coach-button.tsx — NEW. Per-card "Ask Coach about this" CTA
  that returns null when aiEnabled is false. No greyed-out button,
  no tooltip placeholder — the gate is total per Marc's
  "no broken-button state" directive.

Supporting helpers (each unit-tested):
- src/lib/targets/mood-stability-label.ts — pure σ → verbal-label
  threshold logic (< 1.0 stable, < 2.0 variable, ≥ 2.0
  highlyVariable). Thresholds documented in the helper and confirmed
  in the W3e plan.
- src/lib/ai/coach/target-prompts.ts — 8 metric × 2 locale templates
  for the per-card Coach prefill. Falls back to a general template for
  glucose contexts. PROMPT_VERSION unchanged (the assistant-facing
  prompt does not shift; only user-side prefills do).
- src/lib/ai/coach/target-scope.ts — per-target CoachScope.sources
  mapping. Derived metrics (BMI → weight, MOOD_STABILITY → mood) point
  at the underlying source; unmapped targets return an empty array
  so the drawer falls back to defaults.

i18n keys added: targets.consistency.* (cap + dot aria + relative day
+ insufficient-data), targets.card.{lastMet,streak}, targets.relativeDay.*,
targets.summary.{weekTitle,weekTitleAll,streakHighlight},
targets.coach.cta, targets.mood.stability.* — all EN + DE.

Tests: 17 cases across 5 suites (consistency-strip render variants,
target-coach-button gate branches, range-bar zone painting,
target-card full-data + insufficient-data + aiEnabled-off +
MOOD_STABILITY verbal-headline, mood-stability-label thresholds).

Page.tsx still uses the old inline composition for now — Phase 5
wires it to the new components.

src/lib/ai/coach/target-prompts.ts

@@ -0,0 +1,113 @@
+import { moodStabilityLabel } from "@/lib/targets/mood-stability-label";
+
+/**
+ * v1.4.25 W3e — per-target Coach prompt builder.
+ *
+ * Returns a locale-appropriate pre-filled question that seeds the
+ * Coach drawer's composer when the user clicks "Ask Coach about this"
+ * on a target card. The prompt mentions the live current value, the
+ * target range, the user's last-7-day cadence, and the streak (when
+ * present) so the model has enough context to give a grounded answer
+ * even before the snapshot lands.
+ *
+ * Prompts are deliberately question-shaped (not instructions). The
+ * user can rewrite freely; the prefill exists to remove the
+ * cold-start friction of typing the same question every time.
+ *
+ * Six metric templates × two locales = 12 prompts. Glucose contexts
+ * fall back to the "general" template so we don't ship a four-way
+ * context-aware glucose prompt before the iOS rollout decides whether
+ * to surface glucose-by-context in the iOS Targets view.
+ *
+ * NOTE on PROMPT_VERSION: the Coach prompt itself (the system prompt
+ * the model sees) does NOT change with this addition. The pre-fill is
+ * just text the user can edit before sending. PROMPT_VERSION ratchets
+ * when the assistant-facing prompt shifts; pre-fills do not, so we
+ * leave PROMPT_VERSION at 4.23.0. Confirm with Marc if a future
+ * change makes this prefill the canonical first turn.
+ */
+export interface TargetPromptInput {
+  type: string;
+  locale: "en" | "de";
+  current: number | null;
+  range: { min: number; max: number } | null;
+  unit: string;
+  status: string | null;
+  streakDays: number;
+  daysInRange7d: number;
+}
+
+type Template = (input: TargetPromptInput) => string;
+
+function fmt(value: number | null, decimals = 1): string {
+  if (value == null) return "—";
+  return Number(value.toFixed(decimals)).toString();
+}
+
+const TEMPLATES_EN: Record<string, Template> = {
+  BLOOD_PRESSURE: (i) =>
+    `My latest blood pressure reading is ${fmt(i.current, 0)} mmHg systolic and my target band is ${i.range ? `${i.range.min}–${i.range.max} mmHg` : "not set"}. Over the last 7 days I've hit the band on ${i.daysInRange7d} days${i.streakDays >= 3 ? ` (current streak: ${i.streakDays} days)` : ""}. What should I focus on this week?`,
+  BLOOD_PRESSURE_IN_TARGET: (i) =>
+    `My blood pressure has been in target ${i.daysInRange7d} of the last 7 days${i.streakDays >= 3 ? ` (current streak: ${i.streakDays} days)` : ""}. Walk me through what's driving the trend and what I should change.`,
+  WEIGHT: (i) =>
+    `My current weight is ${fmt(i.current)} ${i.unit} and my healthy range is ${i.range ? `${i.range.min}–${i.range.max} ${i.unit}` : "not set"}. Over the last 7 days I've been in range on ${i.daysInRange7d} days. What should I focus on?`,
+  PULSE: (i) =>
+    `My resting pulse is ${fmt(i.current, 0)} ${i.unit} (target band ${i.range ? `${i.range.min}–${i.range.max} ${i.unit}` : "not set"}). How does this compare to a healthy pattern for me and what should I watch for?`,
+  BMI: (i) =>
+    `My current BMI is ${fmt(i.current)} ${i.unit} and the healthy range is ${i.range ? `${i.range.min}–${i.range.max}` : "18.5–24.9"}. How am I trending and what should I focus on?`,
+  MOOD_SCORE: (i) =>
+    `My latest mood score is ${fmt(i.current)} / 5 and my target is ${i.range ? `${i.range.min}+ / 5` : "3.5+ / 5"}. How does my mood compare to recent weeks and what could I try?`,
+  MOOD_STABILITY: (i) => {
+    const label =
+      i.current != null ? moodStabilityLabel(i.current) : "stable";
+    const verbal =
+      label === "stable"
+        ? "stable"
+        : label === "variable"
+          ? "variable"
+          : "highly variable";
+    return `My mood pattern is currently ${verbal}. What does this mean for me and what should I keep an eye on?`;
+  },
+  MEDICATION_COMPLIANCE: (i) =>
+    `My medication adherence is ${fmt(i.current, 0)}% over the last 7 days${i.streakDays >= 3 ? ` (current streak: ${i.streakDays} days at goal)` : ""}. What can I change in my routine?`,
+};
+
+const TEMPLATES_DE: Record<string, Template> = {
+  BLOOD_PRESSURE: (i) =>
+    `Mein letzter Blutdruck-Wert liegt bei ${fmt(i.current, 0)} mmHg systolisch, mein Zielbereich ist ${i.range ? `${i.range.min}–${i.range.max} mmHg` : "nicht festgelegt"}. In den letzten 7 Tagen war ich an ${i.daysInRange7d} Tagen im Bereich${i.streakDays >= 3 ? ` (aktuelle Serie: ${i.streakDays} Tage)` : ""}. Worauf sollte ich diese Woche achten?`,
+  BLOOD_PRESSURE_IN_TARGET: (i) =>
+    `Mein Blutdruck war an ${i.daysInRange7d} von 7 Tagen im Zielbereich${i.streakDays >= 3 ? ` (aktuelle Serie: ${i.streakDays} Tage)` : ""}. Erklär mir bitte, was den Trend treibt und was ich ändern sollte.`,
+  WEIGHT: (i) =>
+    `Mein aktuelles Gewicht ist ${fmt(i.current)} ${i.unit}, mein gesunder Bereich liegt bei ${i.range ? `${i.range.min}–${i.range.max} ${i.unit}` : "nicht festgelegt"}. In den letzten 7 Tagen war ich an ${i.daysInRange7d} Tagen im Bereich. Worauf sollte ich mich konzentrieren?`,
+  PULSE: (i) =>
+    `Mein Ruhepuls ist ${fmt(i.current, 0)} ${i.unit} (Zielbereich ${i.range ? `${i.range.min}–${i.range.max} ${i.unit}` : "nicht festgelegt"}). Wie passt das zu einem gesunden Muster für mich und worauf sollte ich achten?`,
+  BMI: (i) =>
+    `Mein aktueller BMI liegt bei ${fmt(i.current)} ${i.unit}, der gesunde Bereich ist ${i.range ? `${i.range.min}–${i.range.max}` : "18,5–24,9"}. Wie ist mein Trend und worauf sollte ich achten?`,
+  MOOD_SCORE: (i) =>
+    `Mein letzter Stimmungs-Wert ist ${fmt(i.current)} / 5, mein Ziel liegt bei ${i.range ? `${i.range.min}+ / 5` : "3,5+ / 5"}. Wie ist meine Stimmung im Vergleich zu den letzten Wochen, und was könnte ich ausprobieren?`,
+  MOOD_STABILITY: (i) => {
+    const label =
+      i.current != null ? moodStabilityLabel(i.current) : "stable";
+    const verbal =
+      label === "stable"
+        ? "stabil"
+        : label === "variable"
+          ? "schwankend"
+          : "sehr schwankend";
+    return `Mein Stimmungsmuster ist aktuell ${verbal}. Was bedeutet das für mich und worauf sollte ich achten?`;
+  },
+  MEDICATION_COMPLIANCE: (i) =>
+    `Meine Einnahmetreue liegt in den letzten 7 Tagen bei ${fmt(i.current, 0)}%${i.streakDays >= 3 ? ` (aktuelle Serie: ${i.streakDays} Tage im Ziel)` : ""}. Was könnte ich an meiner Routine ändern?`,
+};
+
+const GENERAL_EN: Template = (i) =>
+  `I'd like to understand how I'm doing on ${i.type.toLowerCase().replace(/_/g, " ")} this week. Where am I doing well and where should I focus?`;
+const GENERAL_DE: Template = (i) =>
+  `Wie steht es um meine ${i.type.toLowerCase().replace(/_/g, " ")} diese Woche? Wo läuft es gut und worauf sollte ich achten?`;
+
+export function buildTargetPrompt(input: TargetPromptInput): string {
+  const table = input.locale === "de" ? TEMPLATES_DE : TEMPLATES_EN;
+  const fallback = input.locale === "de" ? GENERAL_DE : GENERAL_EN;
+  const template = table[input.type] ?? fallback;
+  return template(input);
+}

src/lib/ai/coach/target-scope.ts

@@ -0,0 +1,48 @@
+import type { CoachScopeSource } from "@/lib/ai/coach/types";
+
+/**
+ * v1.4.25 W3e — per-target Coach scope source mapping.
+ *
+ * The per-card "Ask Coach about this" CTA narrows the snapshot to the
+ * single source the user is asking about. For derived metrics (BMI
+ * derives from weight; mood stability derives from mood) we map to the
+ * underlying source — the Coach prompt-builder knows how to talk
+ * about the derived view but the data it needs lives in the source.
+ *
+ * Targets without a CoachScopeSource counterpart (glucose contexts,
+ * steps, sleep, body-fat as of v1.4.23) fall back to an empty array,
+ * which the drawer reads as "do not narrow — use defaults". The
+ * Coach defaults already include the five-source set, so the snapshot
+ * stays useful even when this map has no opinion.
+ */
+export function coachScopeForTarget(
+  targetType: string,
+): ReadonlyArray<CoachScopeSource> {
+  switch (targetType) {
+    case "WEIGHT":
+    case "BMI":
+      return ["weight"];
+    case "BLOOD_PRESSURE":
+    case "BLOOD_PRESSURE_IN_TARGET":
+      return ["bp"];
+    case "PULSE":
+      return ["pulse"];
+    case "MOOD_SCORE":
+    case "MOOD_STABILITY":
+      return ["mood"];
+    case "MEDICATION_COMPLIANCE":
+      return ["compliance"];
+    case "SLEEP_DURATION":
+      return ["sleep"];
+    case "ACTIVITY_STEPS":
+      return ["steps"];
+    case "BODY_FAT":
+      // No 1:1 source — the snapshot's weight + general blocks carry
+      // the surrounding context. Empty scope = "use defaults".
+      return [];
+    default:
+      // Glucose contexts + future targets — defaults will surface the
+      // available scopes in the drawer.
+      return [];
+  }
+}

src/lib/targets/__tests__/mood-stability-label.test.ts

@@ -0,0 +1,28 @@
+import { describe, expect, it } from "vitest";
+
+import { moodStabilityLabel } from "../mood-stability-label";
+
+/**
+ * v1.4.25 W3e — threshold contract for the verbal MOOD_STABILITY label.
+ * The card switches from raw σ to one of three buckets; the rule lives
+ * here so the boundaries can be unit-tested without React.
+ */
+
+describe("moodStabilityLabel", () => {
+  it("returns 'stable' for σ below 1.0", () => {
+    expect(moodStabilityLabel(0)).toBe("stable");
+    expect(moodStabilityLabel(0.42)).toBe("stable");
+    expect(moodStabilityLabel(0.999)).toBe("stable");
+  });
+
+  it("returns 'variable' for σ in [1.0, 2.0)", () => {
+    expect(moodStabilityLabel(1.0)).toBe("variable");
+    expect(moodStabilityLabel(1.5)).toBe("variable");
+    expect(moodStabilityLabel(1.999)).toBe("variable");
+  });
+
+  it("returns 'highlyVariable' for σ ≥ 2.0", () => {
+    expect(moodStabilityLabel(2.0)).toBe("highlyVariable");
+    expect(moodStabilityLabel(3.5)).toBe("highlyVariable");
+  });
+});

src/lib/targets/mood-stability-label.ts

@@ -0,0 +1,24 @@
+/**
+ * v1.4.25 W3e — verbal label for the MOOD_STABILITY target headline.
+ *
+ * The card used to render the raw σ value ("0.42 σ"), which most users
+ * cannot interpret. Replace with a three-state verbal label keyed
+ * against translation entries `targets.mood.stability.{stable,
+ * variable,highlyVariable}`.
+ *
+ * Thresholds (Marc-set, documented in the W3e implementation plan):
+ *   σ <  1.0  →  "stable"           (stabil / stable)
+ *   σ <  2.0  →  "variable"         (schwankend / variable)
+ *   σ ≥  2.0  →  "highly-variable"  (sehr schwankend / highly variable)
+ *
+ * Pure helper so the threshold logic can be unit-tested in isolation
+ * without React. Returns the stable English key — callers (the card,
+ * the Coach prompt builder) own the locale resolution.
+ */
+export type MoodStabilityLabel = "stable" | "variable" | "highlyVariable";
+
+export function moodStabilityLabel(sigma: number): MoodStabilityLabel {
+  if (sigma < 1.0) return "stable";
+  if (sigma < 2.0) return "variable";
+  return "highlyVariable";
+}