fix(coach): count distinct sources in the finished steps header

src/components/insights/coach-panel/__tests__/turn-steps.test.tsx

@@ -10,6 +10,7 @@ import type { CoachStep } from "@/lib/ai/coach/types";
 import {
   CoachTurnStepList,
   CoachTurnSteps,
+  countSources,
   currentStep,
   describeStep,
   nextAnnouncement,
@@ -110,7 +111,7 @@ describe("describeStep", () => {
 
   it("renders in the reader's language from the keys, not the server label", () => {
     const de = translators("de");
-    expect(stepLabel(BP, de.t)).toBe("Lese Blutdruck, letzte 90 Tage");
+    expect(stepLabel(BP, de.t)).toBe("Prüfe: Blutdruck, letzte 90 Tage");
     expect(describeStep(BP, de.t, de.tCount).meta).toEqual([
       "letzte 90 Tage",
       "142 Messwerte",
@@ -167,6 +168,28 @@ describe("<CoachTurnSteps>", () => {
     expect(html).not.toContain('data-slot="coach-turn-steps-list"');
   });
 
+  it("counts distinct sources: a second read of the same domain is not a new source", () => {
+    const bpPrevious: CoachStep = {
+      ...BP,
+      id: "s4",
+      period: "previous",
+      count: 120,
+    };
+    const snapshot: CoachStep = {
+      id: "s5",
+      tool: "snapshot",
+      labelKey: "coach.step.snapshot",
+      label: "Overview",
+      status: "done",
+    };
+    expect(countSources([BP, bpPrevious, SLEEP])).toBe(2);
+    expect(countSources([BP, snapshot, snapshot])).toBe(2);
+    const html = render(
+      <CoachTurnSteps steps={[BP, bpPrevious, SLEEP]} active={false} />,
+    );
+    expect(html).toContain("Looked at 2 sources");
+  });
+
   it("carries a polite status region that starts empty", () => {
     const html = render(<CoachTurnSteps steps={[BP]} active={false} />);
     expect(html).toMatch(

src/components/insights/coach-panel/turn-steps.tsx

@@ -118,6 +118,15 @@ function rowText(step: CoachStep, t: Translate, tCount: TranslateCount) {
   return [title, ...meta].join(" · ");
 }
 
+/**
+ * How many sources the turn looked at: one per domain (a step without one,
+ * the snapshot, counts by its tool). A second read of the same domain, for
+ * the period before or a retry, is not a new source.
+ */
+export function countSources(steps: readonly CoachStep[]): number {
+  return new Set(steps.map((step) => step.domain ?? step.tool)).size;
+}
+
 /**
  * The step the active header names: the latest one still running, else the
  * latest one overall (between two rounds nothing is running).
@@ -336,7 +345,7 @@ export function CoachTurnSteps({ steps, active }: CoachTurnStepsProps) {
           </span>
         ) : (
           <span data-slot="coach-turn-steps-done" className="min-w-0 truncate">
-            {tCount("coach.step.headerDone", steps.length)}
+            {tCount("coach.step.headerDone", countSources(steps))}
           </span>
         )}
       </button>