fix(dashboard): mount InsightsCardPreview on root page (wire B1b dashboard preview to live route)

The polished InsightsCardPreview component shipped in B1b commit 5
(d2cdf9d) was an orphan with zero non-test imports. The dashboard read
no advisor payload, so the top severity-ordered AI recommendation +
ring confidence meter + "View all" CTA was unreachable from any live
route. Wave-D design review flagged this as CRITICAL C2.

Wires the preview into the root dashboard page above the chart row,
sharing the advisor cache key with /insights so a regenerate on either
surface refreshes the other without a second LLM call. The preview
self-hides when the user has no provider configured (route 422 → null)
or the advisor returns zero recommendations.

Adds insightsPreview to DASHBOARD_WIDGET_IDS so the layout toggle
persists through Settings → Dashboard. Pins the widget into
DEFAULT_DASHBOARD_LAYOUT (visible: true, tileVisible: false) so users
discover the feature without hunting through settings, and adds a
contract test mirroring the A5 widget-enum-drift guard.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/page.tsx

@@ -46,6 +46,8 @@ import { GettingStartedChecklist } from "@/components/onboarding/getting-started
 import { TourLauncher } from "@/components/onboarding/tour-launcher";
 import { RecentAchievementsCard } from "@/components/gamification/recent-achievements-card";
 import { CompareToggle } from "@/components/comparison/compare-toggle";
+import { InsightsCardPreview } from "@/components/insights/insights-card";
+import { useInsightsAdvisorQuery } from "@/components/insights/use-insights-advisor";
 
 const HealthChart = dynamic(
   () =>
@@ -208,6 +210,17 @@ export default function DashboardPage() {
     enabled: isAuthenticated,
   });
 
+  // v1.4.16 phase D reconcile (CRITICAL C2) — pull the rich advisor
+  // payload so the dashboard can surface a compact preview of the top
+  // severity-ordered AI recommendations + ring confidence meter +
+  // "View all" CTA. Shares the cache with /insights via the
+  // queryKeys.insightsAdvisor() key so a regenerate on either surface
+  // refreshes the other without a second LLM round-trip. Returns null
+  // when the user has no provider configured (route 422 → null), so
+  // the preview self-hides without burning rate-limit tokens on
+  // unconfigured accounts.
+  const advisor = useInsightsAdvisorQuery(isAuthenticated);
+
   const w = data?.summaries?.WEIGHT;
   const sys = data?.summaries?.BLOOD_PRESSURE_SYS;
   const dia = data?.summaries?.BLOOD_PRESSURE_DIA;
@@ -297,6 +310,12 @@ export default function DashboardPage() {
   // the layout-toggle gate here. No data-floor check (the empty card is
   // intentional — Marc wants the user to discover the feature).
   const showAchievementsCard = isChartVisible("achievements");
+  // v1.4.16 phase D reconcile (CRITICAL C2) — gate the dashboard
+  // insights preview by the layout toggle. The component itself
+  // returns null when the advisor payload is missing or has no
+  // recommendations, so the gate is sufficient — no extra data-floor
+  // check needed.
+  const showInsightsPreview = isChartVisible("insightsPreview");
 
   // Glucose widget — visible iff layout enables it AND at least one reading exists.
   // Glucose has no separate chart slot today, so the tile flag is the
@@ -1094,6 +1113,19 @@ export default function DashboardPage() {
                 ))}
               </div>
             )}
+            {/* v1.4.16 phase D reconcile (CRITICAL C2) — dashboard
+                preview of the polished AI recommendations surface.
+                Pinned above the chart row (out-of-band from the sorted
+                charts[] array) so it stays at the top regardless of
+                widget reorder operations. Self-hides when the user has
+                no provider configured OR no recommendations to surface
+                (`<InsightsCardPreview>` returns null), so the preview
+                doesn't paint an empty card on first visit. */}
+            {showInsightsPreview && (
+              <InsightsCardPreview
+                insight={advisor.payload?.insights ?? null}
+              />
+            )}
             {charts.map((entry) => (
               <div key={entry.id} className="space-y-2">
                 {entry.node}

src/components/settings/dashboard-layout-section.tsx

@@ -43,6 +43,10 @@ const WIDGET_LABEL_KEYS: Record<DashboardWidgetId, string> = {
   bpInTarget: "dashboard.bpInTarget",
   oxygenSaturation: "measurements.typeOxygenSaturation",
   achievements: "achievements.title",
+  // v1.4.16 phase D reconcile (CRITICAL C2) — dashboard preview tile
+  // for the polished `<InsightsCardPreview>` (top severity-ordered AI
+  // recommendations + ring confidence meter + "View all" CTA).
+  insightsPreview: "dashboard.insightsPreview",
 };
 
 export function DashboardLayoutSection({ id }: { id: string }) {

src/lib/__tests__/dashboard-layout.test.ts

@@ -141,6 +141,15 @@ describe("DEFAULT_DASHBOARD_LAYOUT contract", () => {
     expect(ids).toContain("achievements");
   });
 
+  it("includes the insightsPreview widget (v1.4.16 phase D reconcile C2)", () => {
+    // CRITICAL C2: dashboard preview of the polished AI recommendations
+    // surface. Same Zod-enum-drift trap as A5 — if the widget id isn't
+    // listed here, the API PUT silently 422s and the layout toggle
+    // never persists. Pin the contract to catch a regression early.
+    const ids = DEFAULT_DASHBOARD_LAYOUT.widgets.map((w) => w.id);
+    expect(ids).toContain("insightsPreview");
+  });
+
   it("survives a round-trip through serialize → resolve unchanged", () => {
     // The API persists `serializeDashboardLayout(parsed.data)` and
     // reads back via `resolveDashboardLayout(row.dashboardWidgetsJson)`.

src/lib/dashboard-layout.ts

@@ -29,6 +29,11 @@ export const DASHBOARD_WIDGET_IDS = [
   "bpInTarget",
   "oxygenSaturation",
   "achievements",
+  // v1.4.16 phase D reconcile (CRITICAL C2) — dashboard preview of the
+  // top severity-ordered AI recommendations + "View all" CTA. Has only
+  // a `visible` (chart-row) surface; tileVisible is forced false because
+  // there's no tile-strip representation for it.
+  "insightsPreview",
 ] as const;
 
 export type DashboardWidgetId = (typeof DASHBOARD_WIDGET_IDS)[number];
@@ -124,6 +129,17 @@ export const DEFAULT_DASHBOARD_LAYOUT: DashboardLayout = {
     // `tileVisible` is forced false because there is no tile surface
     // for this widget; only the chart-row card.
     { id: "achievements", visible: true, tileVisible: false, order: 13 },
+    // v1.4.16 phase D reconcile (CRITICAL C2) — AI insights preview
+    // anchored at the top of the chart row. Default visible so users
+    // discover the feature without hunting through Settings →
+    // Dashboard; self-gates on having a generated payload AND at least
+    // one recommendation (`<InsightsCardPreview>` returns null
+    // otherwise). `tileVisible` forced false because the preview lives
+    // in the chart row, not the tile strip. The dashboard page
+    // renders this entry independently of the sorted `charts[]` array
+    // so it stays pinned above charts even if the user reorders other
+    // widgets; only the boolean visibility flag is consumed.
+    { id: "insightsPreview", visible: true, tileVisible: false, order: 14 },
   ],
 };