Move tag camera and download buttons to a bar instead of floating

lib/dev_config.dart

@@ -13,6 +13,11 @@ const double kDirectionConeBaseLength = 0.0012; // multiplier
 // Add Camera pin vertical offset (for pin tip to match coordinate on map)
 const double kAddPinYOffset = -16.0;
 
+// Bottom overlay vertical positions (distance from bottom of screen)
+const double kAttributionBottom = 5.0;
+const double kScaleBarBottom = 40.0;
+const double kZoomIndicatorBottom = 70.0;
+
 // Client name and version for OSM uploads ("created_by" tag)
 const String kClientName = 'FlockMap';
 const String kClientVersion = '0.8.1';

lib/screens/home_screen.dart

@@ -27,10 +27,12 @@ class _HomeScreenState extends State<HomeScreen> {
   void _openAddCameraSheet() {
     final appState = context.read<AppState>();
     appState.startAddSession();
-    final session = appState.session!;          // guaranteed non‑null now
+    final session = appState.session!; // guaranteed non‑null now
 
-    _scaffoldKey.currentState!.showBottomSheet(
+    showModalBottomSheet(
-      (ctx) => AddCameraSheet(session: session),
+      context: context,
+      isScrollControlled: true,
+      builder: (ctx) => AddCameraSheet(session: session),
     );
   }
 
@@ -66,31 +68,49 @@ class _HomeScreenState extends State<HomeScreen> {
             if (_followMe) setState(() => _followMe = false);
           },
         ),
-        floatingActionButton: appState.session == null
+        bottomNavigationBar: BottomAppBar(
-            ? Column(
+          elevation: 10,
-                mainAxisSize: MainAxisSize.min,
+          child: Padding(
-                crossAxisAlignment: CrossAxisAlignment.end,
+            padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
-                children: [
+            child: Row(
-                  FloatingActionButton.extended(
+              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
-                    onPressed: _openAddCameraSheet,
+              children: [
+                Expanded(
+                  child: ElevatedButton.icon(
                     icon: const Icon(Icons.add_location_alt),
                     label: const Text('Tag Camera'),
-                    heroTag: 'tag_camera_fab',
+                    onPressed: () {
-                  ),
+                      if (appState.session == null) {
-                  const SizedBox(height: 12),
+                        _openAddCameraSheet();
-                  FloatingActionButton.extended(
+                      }
-                    onPressed: () => showDialog(
+                    },
-                      context: context,
+                    style: ElevatedButton.styleFrom(
-                      builder: (ctx) => DownloadAreaDialog(controller: _mapController),
+                      minimumSize: const Size(0, 48),
+                      textStyle: const TextStyle(fontSize: 16),
                     ),
+                  ),
+                ),
+                const SizedBox(width: 12),
+                Expanded(
+                  child: ElevatedButton.icon(
                     icon: const Icon(Icons.download_for_offline),
                     label: const Text('Download'),
-                    heroTag: 'download_fab',
+                    onPressed: appState.session == null
+                      ? () => showDialog(
+                          context: context,
+                          builder: (ctx) => DownloadAreaDialog(controller: _mapController),
+                        )
+                      : null, // Disabled while camera sheet active
+                    style: ElevatedButton.styleFrom(
+                      minimumSize: const Size(0, 48),
+                      textStyle: const TextStyle(fontSize: 16),
+                    ),
                   ),
-                ],
+                ),
-              )
+              ],
-            : null,
+            ),
-        floatingActionButtonLocation: FloatingActionButtonLocation.endFloat,
+          ),
+        ),
       ),
     );
   }

lib/widgets/map_view.dart

@@ -311,7 +311,7 @@ class _MapViewState extends State<MapView> {
             // Built-in scale bar from flutter_map 
             Scalebar(
               alignment: Alignment.bottomLeft,
-              padding: EdgeInsets.only(left: 8, bottom: 54), // above attribution
+              padding: EdgeInsets.only(left: 8, bottom: kScaleBarBottom), // from dev_config, above attribution & BottomAppBar
               textStyle: TextStyle(color: Colors.black, fontWeight: FontWeight.bold),
               lineColor: Colors.black,
               strokeWidth: 3,
@@ -353,7 +353,7 @@ class _MapViewState extends State<MapView> {
         // Zoom indicator, positioned above scale bar
         Positioned(
           left: 10,
-          bottom: 92,
+          bottom: kZoomIndicatorBottom, // from dev_config
           child: Container(
             padding: const EdgeInsets.symmetric(horizontal: 7, vertical: 2),
             decoration: BoxDecoration(
@@ -377,7 +377,7 @@ class _MapViewState extends State<MapView> {
         ),
         // Attribution overlay
         Positioned(
-          bottom: 20,
+          bottom: kAttributionBottom, // from dev_config
           left: 10,
           child: Container(
             color: Colors.white70,