v0.1.5 — remove Waze entirely

Waze's reCAPTCHA gating on live-map/api/georss has no clean mobile
workaround, and the Citizen source added in v0.1.4 covers the same
threat model with better data. Keeping a permanently-failed source
visible was UI clutter — drop it.

Removed:
  - scan/WazeClient.kt and scan/WazeScanner.kt (deleted)
  - WAZE from DetectionSource enum
  - waze flow from SourceHealth (+ flowFor/record/reset cases)
  - WazeObservation + scoreWaze + W_WAZE_POLICE from ConfidenceEngine
  - wazeEnabled from Settings (+ KEY_WAZE)
  - WAZE row from SettingsScreen
  - wazeScanner from DetectionService

Renamed (Citizen now owns the proximity slider that Waze used to share):
  - Settings.wazeProximityM → citizenProximityM
  - Settings.setWazeProximityM → setCitizenProximityM
  - KEY_WAZE_PROX → KEY_CITIZEN_PROX
  - DEFAULT_WAZE_PROX → DEFAULT_CITIZEN_PROX (still 500)
  - SettingsScreen "Waze alert distance" → "Citizen alert distance"

Existing users will see the slider reset to 500 m default since the
SharedPreferences key changed.

versionCode 5 → 6, versionName 0.1.4 → 0.1.5.

app/build.gradle.kts

@@ -12,8 +12,8 @@ android {
         applicationId = "org.soulstone.overwatch"
         minSdk = 26
         targetSdk = 35
-        versionCode = 5
-        versionName = "0.1.4"
+        versionCode = 6
+        versionName = "0.1.5"
     }
 
     buildTypes {