android: home phase 2 - events inbox and problem notifications

- EventLog keeps what the app noticed and did by itself for 30 days on the
  device (events.json); repeats of the same event within 30 minutes are
  merged (x3), problems that go away are marked resolved.
- Recorded: connection errors and recovery, carrier whitelists on/off,
  health-check reconnects, auto-connect starting/parking the tunnel, the
  end of a pause, available updates.
- Problems are pushed on a new "Connection problems" channel, but only
  while the app is in the background (Home shows them already).
- «Events» screen (InboxActivity): filters (all, need attention,
  connection, routes, app), grouped by day, one action per event; opened
  from a bell with an unread badge in the Home header.
- Amber warning colours in the status palette, used for whitelists, no
  network and an unresponsive server.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/frontends/android/app/src/main/AndroidManifest.xml

@@ -129,6 +129,10 @@
 			android:name=".ui.RouteCheckActivity"
 			android:label="@string/route_check_title">
 		</activity>
+		<activity
+			android:name=".ui.InboxActivity"
+			android:label="@string/events_title">
+		</activity>
         <activity
             android:name=".ui.RemediationInstructionsActivity"
             android:label="@string/remediation_instructions_title" >