fix(social): prevent horizontal overflow in GPX export snackbar (#52)

- Wrap GPX export snackbar message Text in Expanded with maxLines: 2 and TextOverflow.ellipsis

- Add ValueKey('gpx_export_button_<id>') for deterministic testing

- Wrap narrow feed header/metric/empty-state Row labels in Flexible to prevent overflow under 320px/360px at 1.5x text scale

- Add BUG-005 widget tests across 320x640, 360x800, and 800x480 viewports at 1.5x text scale

lib/features/social/feed/social_feed_screen.dart

@@ -252,7 +252,8 @@ class _SocialFeedScreenState extends ConsumerState<SocialFeedScreen> {
             crossAxisAlignment: CrossAxisAlignment.center,
             children: [
               // Status LED pill
-              Container(
+              Flexible(
+                child: Container(
                   padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 5),
                   decoration: BoxDecoration(
                     color: colors.surfaceCardSecondary,
@@ -273,8 +274,11 @@ class _SocialFeedScreenState extends ConsumerState<SocialFeedScreen> {
                         ),
                       ),
                       const SizedBox(width: 8),
-                    Text(
+                      Flexible(
+                        child: Text(
                           'SQUAD & CANYON FEED',
+                          maxLines: 1,
+                          overflow: TextOverflow.ellipsis,
                           style: TextStyle(
                             fontFamily: AppTypography.fontTelemetry,
                             fontSize: 11,
@@ -283,9 +287,11 @@ class _SocialFeedScreenState extends ConsumerState<SocialFeedScreen> {
                             color: accentColor,
                           ),
                         ),
+                      ),
                     ],
                   ),
                 ),
+              ),
 
               // Search toggle button
               IconButton(
@@ -1358,19 +1364,26 @@ class _SocialFeedCardState extends ConsumerState<_SocialFeedCard>
 
                     // GPX Export Button
                     InkWell(
+                      key: ValueKey('gpx_export_button_${item.id}'),
                       borderRadius: BorderRadius.circular(12),
                       onTap: () {
                         ScaffoldMessenger.of(context).showSnackBar(
                           SnackBar(
-                            backgroundColor: const Color(0xFF1D2025),
+                            backgroundColor: colors.surfaceCardSecondary,
                             content: Row(
                               children: [
-                                const Icon(Icons.download_done_rounded,
+                                Icon(
-                                    color: AppColors.electricCyan),
+                                  Icons.download_done_rounded,
+                                  color: accentColor,
+                                ),
                                 const SizedBox(width: 10),
-                                Text(
+                                Expanded(
+                                  child: Text(
                                     'GPX track exported for ${item.rideTitle}',
-                                  style: const TextStyle(color: Colors.white),
+                                    maxLines: 2,
+                                    overflow: TextOverflow.ellipsis,
+                                    style: TextStyle(color: colors.textPrimary),
+                                  ),
                                 ),
                               ],
                             ),
@@ -1519,7 +1532,8 @@ class _SocialFeedCardState extends ConsumerState<_SocialFeedCard>
                 ),
                 if (unit.isNotEmpty) ...[
                   const SizedBox(width: 4),
-                  Text(
+                  Flexible(
+                    child: Text(
                       unit,
                       maxLines: 1,
                       overflow: TextOverflow.ellipsis,
@@ -1530,6 +1544,7 @@ class _SocialFeedCardState extends ConsumerState<_SocialFeedCard>
                         color: secondaryTextColor,
                       ),
                     ),
+                  ),
                 ],
               ],
             ),
@@ -1568,6 +1583,7 @@ class _SocialFeedCardState extends ConsumerState<_SocialFeedCard>
               child: Center(
                 child: Container(
                   key: ValueKey('feed_route_no_gps_state_${item.id}'),
+                  margin: const EdgeInsets.symmetric(horizontal: 12),
                   padding: const EdgeInsets.symmetric(
                     horizontal: 12,
                     vertical: 6,
@@ -1588,8 +1604,11 @@ class _SocialFeedCardState extends ConsumerState<_SocialFeedCard>
                         color: Color(0xFF94A3B8),
                       ),
                       SizedBox(width: 6),
-                      Text(
+                      Flexible(
+                        child: Text(
                           'NO GPS TRACK RECORDED',
+                          maxLines: 1,
+                          overflow: TextOverflow.ellipsis,
                           style: TextStyle(
                             fontFamily: AppTypography.fontTelemetry,
                             fontSize: 10,
@@ -1598,6 +1617,7 @@ class _SocialFeedCardState extends ConsumerState<_SocialFeedCard>
                             color: Color(0xFFCBD5E1),
                           ),
                         ),
+                      ),
                     ],
                   ),
                 ),

test/community_social_feed_test.dart

@@ -901,4 +901,83 @@ void main() {
       );
     }
   });
+
+  group('BUG-005: GPX Export Snackbar Horizontal Overflow Tests', () {
+    for (final viewport in const [
+      Size(320, 640),
+      Size(360, 800),
+      Size(800, 480),
+    ]) {
+      testWidgets(
+        'GPX export snackbar renders long rideTitle without RenderFlex overflow at ${viewport.width.toInt()}x${viewport.height.toInt()} (1.5x text scale)',
+        (tester) async {
+          await tester.binding.setSurfaceSize(viewport);
+
+          final service = SocialFeedService();
+          addTearDown(service.dispose);
+
+          const longRideTitle =
+              'Ultra Long Sunday Skyline Boulevard & Pescadero Creek Canyon Telemetry Endurance Carve Session With Full Squad Pack';
+
+          final post = await service.shareRecentRide(
+            authorUid: 'uid_overflow_test',
+            authorDisplayName: 'Marcus Vance',
+            authorHandle: 'ApexMarcus',
+            locationName: 'Skyline Blvd',
+            rideTitle: longRideTitle,
+            bikeModel: '2024 Ducati Streetfighter V4',
+            distanceMiles: 68.4,
+            durationSeconds: 4440,
+            maxLeanAngleDeg: 51.0,
+          );
+
+          await tester.pumpWidget(
+            ProviderScope(
+              overrides: [
+                socialFeedServiceProvider.overrideWithValue(service),
+              ],
+              child: MediaQuery(
+                data: MediaQueryData(
+                  size: viewport,
+                  textScaler: const TextScaler.linear(1.5),
+                ),
+                child: MaterialApp(
+                  theme: ThemeData.dark().copyWith(
+                    extensions: const [MotorSignalThemeColors.dark],
+                  ),
+                  home: const SocialFeedScreen(),
+                ),
+              ),
+            ),
+          );
+          await tester.pump();
+          await tester.pump(const Duration(milliseconds: 50));
+
+          final gpxButton = find.byKey(
+            ValueKey('gpx_export_button_${post.id}'),
+          );
+          await tester.scrollUntilVisible(
+            gpxButton,
+            120.0,
+            scrollable: find.descendant(
+              of: find.byKey(const ValueKey('social_feed_list_view')),
+              matching: find.byType(Scrollable),
+            ),
+          );
+          await tester.pumpAndSettle();
+
+          await tester.tap(gpxButton);
+          await tester.pump();
+          await tester.pump(const Duration(milliseconds: 300));
+
+          // Must not throw any RenderFlex overflow exception
+          expect(tester.takeException(), isNull);
+          expect(
+            find.text('GPX track exported for $longRideTitle'),
+            findsOneWidget,
+          );
+        },
+      );
+    }
+  });
 }