Add allowed-window restriction and harden daily location

[patriciojofre]

Summary

Restricts the daily-location report to a server-configured time window and hardens the surrounding flow. The window comes from settings.local.location_schedule in /devices/:key/status.json and is evaluated in UTC. With no config, the location is still sent daily ASAP (unchanged behavior).

Config shape:

{
  "start_at": "10:00", "end_at": "11:00",
  "sunday": false, "monday": true, "tuesday": true, "wednesday": true,
  "thursday": true, "friday": true, "saturday": false
}

Changes

New allowed-window restriction

• LocationScheduleWindow (new, pure/unit-tested): isWithinAllowedWindow(scheduleJson, now) evaluated in UTC — per-weekday booleans (no flags → any day; otherwise only true days) and inclusive start_at/end_at. Empty/absent/malformed config → send ASAP (fail-open).
• PreyStatus.initConfig() parses settings.local.location_schedule; PreyConfig gains the LOCATION_SCHEDULE key with get/set.

Hardening / fixes

• UTC day boundary: DailyLocation uses a dedicated UTC yyyy-MM-dd formatter for the "already sent today" guard and the success write (leaves the shared FORMAT_SDF_AWARE used by the Aware system untouched).
• Doze resilience: LocationScheduled replaces setInexactRepeating with a self-rescheduling setAndAllowWhileIdle (API 23+) / setExact (21–22) alarm; AlarmLocationReceiver re-arms the next fire before running so a failure can't break the schedule.
• Acquisition: 6 attempts with longer sleeps, keeps the most-accurate fix, breaks early at ≤50 m, and sends the best fix obtained rather than skipping the day.
• Cleanup: replaced throw new RuntimeException(e) with logging; removed the duplicate setLastLocation(null).

Guard order in DailyLocation.run: already-sent-today (UTC) → skip · airplane mode OR outside window → skip · else acquire + send · store UTC date only on HTTP 200/201 → one send per allowed UTC day.

Testing

• New LocationScheduleWindowTest (Robolectric): 12 tests, all passing — no/empty/malformed config, day in/out, time before/in/after, inclusive boundaries, days-only, hours-only.
• ./gradlew :app:compileDebugJavaWithJavac clean; targeted unit tests green.
• Not exercised on a device: end-to-end alarm→fix→POST and Doze firing of setAndAllowWhileIdle. Also worth confirming the exact location_schedule key/shape the server emits under settings.local.