fix(gps): Genauigkeitsanzeige unter und ab 100 m unterscheiden

Der tote Ternär lieferte in beiden Zweigen dieselbe Rundung; ab 100 m
wird jetzt auf 10 m gerundet, damit schwache Fixes nicht falsch präzise wirken.

Co-authored-by: Cursor <cursoragent@cursor.com>

client/src/utils/geolocation.test.ts

@@ -1,6 +1,7 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import {
   classifyGpsAccuracyMeters,
+  formatGpsAccuracyMeters,
   geolocationErrorI18nKey,
   GEOLOCATION_LIVE_INTRO_STORAGE_KEY,
   getCurrentPosition,
@@ -81,6 +82,13 @@ describe('geolocation helpers', () => {
     })
   })
 
+  it('formats GPS accuracy for display', () => {
+    expect(formatGpsAccuracyMeters(12.4)).toBe('12')
+    expect(formatGpsAccuracyMeters(87)).toBe('87')
+    expect(formatGpsAccuracyMeters(105)).toBe('110')
+    expect(formatGpsAccuracyMeters(247)).toBe('250')
+  })
+
   it('classifies GPS accuracy into signal quality', () => {
     expect(classifyGpsAccuracyMeters(8)).toBe('excellent')
     expect(classifyGpsAccuracyMeters(30)).toBe('good')

client/src/utils/geolocation.ts

@@ -30,8 +30,11 @@ export function gpsQualityI18nKey(quality: GpsSignalQuality): string {
   return `logs.gps_quality_${quality}`
 }
 
+/** Formats accuracy for i18n (±{{accuracy}} m): 1 m below 100 m, 10 m from 100 m upward. */
 export function formatGpsAccuracyMeters(accuracyM: number): string {
-  return accuracyM < 100 ? String(Math.round(accuracyM)) : String(Math.round(accuracyM))
+  return accuracyM < 100
+    ? String(Math.round(accuracyM))
+    : String(Math.round(accuracyM / 10) * 10)
 }
 
 export type GeolocationPermissionState = PermissionState | 'unsupported'