Add shared UI components for mesh application

- Introduced `mesh_ui.dart` with reusable widgets including SectionHeader, MeshCard, StatusChip, StatTile, AvatarCircle, SignalBars, RouteChip, PulseDot, BottomSheetHeader, ErrorRetryCard, and ListEntrance.
- Implemented `path_map_ui.dart` for path map screens, featuring path distance calculations, playback controls, and a summary list of observed paths.
- Created `themed_map_tile_layer.dart` for shared cached map tiles with automatic dark-mode treatment.

lib/widgets/message_status_icon.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter_svg/flutter_svg.dart';
 
 import '../l10n/l10n.dart';
+import '../theme/mesh_theme.dart';
 
 class MessageStatusIcon extends StatefulWidget {
   final bool isAcked;
@@ -71,7 +72,11 @@ class _MessageStatusIconState extends State<MessageStatusIcon>
     if (widget.isFailed) {
       return Semantics(
         label: l10n.messageStatus_failed,
-        child: Icon(Icons.cancel, size: size, color: colorScheme.error),
+        child: Icon(
+          Icons.cancel,
+          size: size,
+          color: colorScheme.error,
+        ),
       );
     }
 
@@ -92,7 +97,10 @@ class _MessageStatusIconState extends State<MessageStatusIcon>
         : widget.isAcked
         ? l10n.messageStatus_delivered
         : l10n.messageStatus_sent;
-    final Color color = delivered ? colorScheme.tertiary : baseColor;
+    // Use palette colors: tertiary (warn/amber) for acked/repeated, base for sent.
+    final Color color = delivered
+        ? MeshPalette.signal.withValues(alpha: 0.9)
+        : baseColor;
 
     return Semantics(
       label: label,