fix(google-health): round imported values through importValue

The mapper kept its own parseFloat(n.toFixed(2)), which rounds a half at
the third decimal down whenever the double sits just below it: a weight of
72 345 g stored as 72.34 kg, a distance of 1 000 005 mm as 1000 m. The
shared importValue rounds on the decimal the value prints as. The rounding
guard drops its last pending entry and also catches a round2 declared as a
const.

src/__tests__/provider-rounding-guard.test.ts

@@ -26,17 +26,7 @@ const PROVIDER_DIRS = [
   "whoop",
   "withings",
 ];
-/**
- * Files that still round on their own, with the reason. Google Health's
- * mapper is the one left: it moves to `importValue` with the next change to
- * that directory.
- */
-const PENDING: Readonly<Record<string, string>> = {
-  "google-health/mappers.ts":
-    "moves to importValue with the next Google Health change",
-};
-
-const ROUNDING = /\.toFixed\s*\(|\bfunction\s+round2\b/;
+const ROUNDING = /\.toFixed\s*\(|\b(?:function|const|let)\s+round2\b/;
 
 function strip(text: string): string {
   return text
@@ -56,25 +46,17 @@ describe("provider clients round through importValue", () => {
     expect(files.length).toBeGreaterThanOrEqual(60);
   });
 
-  it("finds no rounding of their own outside the pending list", () => {
-    const offenders = files.filter(
-      (f) =>
-        !(f in PENDING) &&
-        ROUNDING.test(strip(readFileSync(join(LIB, f), "utf8"))),
+  it("finds no rounding of their own", () => {
+    const offenders = files.filter((f) =>
+      ROUNDING.test(strip(readFileSync(join(LIB, f), "utf8"))),
     );
     expect(offenders).toEqual([]);
   });
 
-  it("keeps the pending list honest", () => {
-    const stale = Object.keys(PENDING).filter(
-      (f) => !ROUNDING.test(strip(readFileSync(join(LIB, f), "utf8"))),
-    );
-    expect(stale).toEqual([]);
-  });
-
   it("catches a planted copy", () => {
     expect(ROUNDING.test("const v = parseFloat(n.toFixed(2));")).toBe(true);
     expect(ROUNDING.test("function round2(n: number) {}")).toBe(true);
+    expect(ROUNDING.test("const round2 = (n: number) => n;")).toBe(true);
     expect(ROUNDING.test("value: importValue(n)")).toBe(false);
   });
 });

src/lib/google-health/__tests__/mappers.test.ts

@@ -73,6 +73,43 @@ describe("mapWeight — spot sample", () => {
   });
 });
 
+describe("imported values round half away from zero (importValue)", () => {
+  // Each of these sits on a half at the third decimal whose double lies just
+  // below it, where `toFixed(2)` rounded down.
+  it("rounds a gram-precise weight up on the half", () => {
+    const [r] = mapWeight({
+      weight: {
+        weightGrams: 72345,
+        sampleTime: { physicalTime: "2026-06-01T08:00:00.000Z" },
+      },
+    });
+    expect(r!.value).toBe(72.35);
+  });
+
+  it("rounds a daily distance total up on the half", () => {
+    const [r] = mapDistance({
+      civilStartTime: { date: { year: 2026, month: 6, day: 1 } },
+      distance: { millimetersSum: "1000005" },
+    });
+    expect(r!.value).toBe(1000.01);
+  });
+
+  it("rounds a session distance up on the half", () => {
+    const w = mapWorkout({
+      name: "users/me/dataTypes/exercise/dataPoints/half",
+      exercise: {
+        exerciseType: "RUNNING",
+        interval: {
+          startTime: "2026-06-03T07:00:00.000Z",
+          endTime: "2026-06-03T07:45:00.000Z",
+        },
+        metricsSummary: { distanceMillimeters: "8000025" },
+      },
+    });
+    expect(w!.totalDistanceM).toBe(8000.03);
+  });
+});
+
 describe("mapBodyFat — camelCase union key", () => {
   it("reads the percentage under the camelCase bodyFat key", () => {
     const rows = mapBodyFat({

src/lib/google-health/mappers.ts

@@ -14,6 +14,7 @@
  * this file performs I/O — everything is synchronous and deterministic given a
  * payload (+ optional user timezone).
  */
+import { importValue } from "@/lib/integrations/import-value";
 import { canonicalDailyTimestamp } from "@/lib/measurements/consolidation-tz";
 import { zonedWallClockToUtc } from "@/lib/tz/wall-clock";
 
@@ -217,10 +218,6 @@ export interface GoogleHealthRollupPoint {
 /** Millimetres → centimetres (Google `height.heightMillimeters` → `User.heightCm`). */
 const MM_TO_CM = 0.1;
 
-function round2(n: number): number {
-  return parseFloat(n.toFixed(2));
-}
-
 /**
  * Coerce a raw payload value to a finite number, or null. proto3 int64 fields
  * arrive as JSON strings (`"12345"`); `Number()` handles both int and decimal
@@ -445,7 +442,7 @@ function mapSimple(
   return [
     {
       type: spec.type,
-      value: round2(value),
+      value: importValue(value),
       unit: spec.unit,
       measuredAt: resolveMeasuredAt(point, dataType, new Date(), tz),
       fieldTag: `${externalAnchor(point, dataType)}:${spec.fieldTag}`,
@@ -678,7 +675,7 @@ export function mapHeight(
   if (mm === null) return null;
   const t = readPath(point, `${dt.key}.sampleTime.physicalTime`);
   const sampledAt = typeof t === "string" ? parseLocalInstant(t) : null;
-  return { cm: round2(mm * MM_TO_CM), sampledAt };
+  return { cm: importValue(mm * MM_TO_CM), sampledAt };
 }
 
 // ─── Activity mappers: daily roll-up totals ────────────────────
@@ -732,7 +729,7 @@ function mapDailyRollup(
   return [
     {
       type: spec.type,
-      value: round2(value),
+      value: importValue(value),
       unit: spec.unit,
       measuredAt: canonicalDailyTimestamp(dayKey, tz),
       // `stats:<type-tag>:<YYYY-MM-DD>` — the sync layer reads `cumulativeDaily`
@@ -833,7 +830,7 @@ export function mapVo2Max(
   return [
     {
       type: "VO2_MAX",
-      value: round2(value),
+      value: importValue(value),
       unit: "mL/(kg·min)",
       measuredAt,
       fieldTag: `vo2_max:${externalAnchor(point, dt)}`,
@@ -1035,7 +1032,7 @@ export function mapSleepSessionDetailed(
     if (!windowEnd || end > windowEnd) windowEnd = end;
     rows.push({
       type: "SLEEP_DURATION",
-      value: round2(mins),
+      value: importValue(mins),
       unit: "minutes",
       measuredAt: end,
       fieldTag: `${anchor}:sleep:${start.toISOString()}`,
@@ -1287,7 +1284,9 @@ export function mapWorkout(
     durationSec,
     totalEnergyKcal: energyKcal !== null ? Math.round(energyKcal) : null,
     totalDistanceM:
-      distanceMm !== null && distanceMm >= 0 ? round2(distanceMm / 1000) : null,
+      distanceMm !== null && distanceMm >= 0
+        ? importValue(distanceMm / 1000)
+        : null,
     avgHeartRate: avgHr !== null && avgHr > 0 ? Math.round(avgHr) : null,
     // metricsSummary carries no maximum/minimum heart rate.
     maxHeartRate: null,