Log Custom API host only, quiet disabled path, note offline iata semantics

Review follow-ups on the offline Custom API forward:
- Log the endpoint host instead of the full URL — debug log files are
  uploaded with bug reports and custom endpoint URLs may embed tokens.
- Skip the "Forward requested/skipped" logging entirely when the Custom
  API feature is disabled (no per-flush noise for users who never
  enabled it).
- Document that offline batches are stamped with the upload-location
  zone, not the record-location zone.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BaNcifvtSbfDh5v538ExxL

Author: MrAlders0n

lib/providers/app_state_provider.dart

@@ -5242,6 +5242,10 @@ class AppStateProvider extends ChangeNotifier with WidgetsBindingObserver {
   }
 
   /// Forward a successfully uploaded offline batch to the Custom API endpoint.
+  ///
+  /// The whole batch is stamped with the upload-location zone (the fresh
+  /// /auth at the current GPS position), not where the pings were recorded —
+  /// the client cannot compute per-ping zones for sessions that span regions.
   void _forwardOfflineBatchToCustomApi(
     List<Map<String, dynamic>> batch, {
     required int batchNum,

lib/services/custom_api_service.dart

@@ -52,13 +52,11 @@ class CustomApiService {
     if (pings.isEmpty) return;
 
     final prefs = _prefsGetter();
+    if (!prefs.customApiEnabled) return;
+
     debugLog(
         '[CUSTOM API] Forward requested ($source): ${pings.length} item(s)');
 
-    if (!prefs.customApiEnabled) {
-      debugLog('[CUSTOM API] Forward skipped ($source): Custom API disabled');
-      return;
-    }
     if (prefs.customApiUrl == null || prefs.customApiUrl!.isEmpty) {
       debugLog('[CUSTOM API] Forward skipped ($source): URL not configured');
       return;
@@ -74,8 +72,12 @@ class CustomApiService {
         : null;
     final iata = iataOverride ?? iataGetter?.call();
 
-    debugLog(
-        '[CUSTOM API] Forwarding ($source) → ${prefs.customApiUrl} '
+    // Log the endpoint host only — the full URL may embed auth tokens, and
+    // debug log files are uploaded verbatim with bug reports.
+    var endpointHost = Uri.tryParse(prefs.customApiUrl!)?.host ?? '';
+    if (endpointHost.isEmpty) endpointHost = 'custom endpoint';
+
+    debugLog('[CUSTOM API] Forwarding ($source) → $endpointHost '
         '(contact=${contact ?? "off"}, iata=${iata ?? "none"})');
 
     final enriched = pings.map((ping) {