v0.2.4: fix countdown notification not appearing + wrong time-remaining

Countdown notification "nothing appears" on session start:
- The small icon was the adaptive launcher mipmap (applicationInfo.icon),
  which Android 13+/GrapheneOS rejects as an invalid notification small icon
  and drops the post silently. Ship a proper white-on-transparent vector
  small icon (bbp_stat_parking) inside the module and use it.
- showCountdown now returns a diagnostic string (posted / notifications
  disabled / exception) instead of swallowing failures; JS logs the branch,
  permission result, and native outcome to the in-app diagnostics log.
- Log the raw active-session payload in refreshSessionStatus (element shape
  was previously unconfirmed).

Time remaining showed "7694 min":
- API's TimeRemaining is SECONDS, not minutes. Format it as hours+minutes
  in SessionDetail; annotate the type.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

parksmarter-client/src/types.ts

@@ -488,6 +488,7 @@ export interface ActiveSession {
   EndTime?: string;
   StartTimeDisplay?: string;
   EndTimeDisplay?: string;
+  /** Seconds left on the session (CONFIRMED via a live session — NOT minutes). */
   TimeRemaining?: number | string;
   VehiclePlate?: string;
   VehicleNumber?: string;