Initial commit: COPILOT D6 Flutter keyboard controller

Flutter web app replacing legacy WPF CCTV surveillance keyboard controller.
Includes wall overview, section view with monitor grid, camera input,
PTZ control, alarm/lock/sequence BLoCs, and legacy-matching UI styling.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

copilot_keyboard/lib/presentation/screens/main_screen.dart

@@ -0,0 +1,168 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+
+import '../blocs/wall/wall_bloc.dart';
+import '../blocs/wall/wall_event.dart';
+import '../blocs/wall/wall_state.dart';
+import '../widgets/overview/wall_overview.dart';
+import '../widgets/section/section_view.dart';
+
+class MainScreen extends StatefulWidget {
+  const MainScreen({super.key});
+
+  @override
+  State<MainScreen> createState() => _MainScreenState();
+}
+
+class _MainScreenState extends State<MainScreen> {
+  String? _selectedSectionId;
+  final FocusNode _focusNode = FocusNode();
+  WallBloc? _wallBloc;
+
+  @override
+  void dispose() {
+    _focusNode.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return BlocBuilder<WallBloc, WallState>(
+      builder: (blocContext, state) {
+        // Store bloc reference for keyboard handler
+        _wallBloc = BlocProvider.of<WallBloc>(blocContext, listen: false);
+
+        return KeyboardListener(
+          focusNode: _focusNode,
+          autofocus: true,
+          onKeyEvent: _handleKeyEvent,
+          child: Scaffold(
+            backgroundColor: const Color(0xFF0A0E14),
+            body: _buildBody(blocContext, state),
+          ),
+        );
+      },
+    );
+  }
+
+  Widget _buildBody(BuildContext context, WallState state) {
+    if (state.isLoading || state.config == null) {
+      return const Center(
+        child: CircularProgressIndicator(
+          color: Color(0xFF00D4FF),
+        ),
+      );
+    }
+
+    // Show section view or wall overview
+    if (_selectedSectionId != null) {
+      final section = state.config!.sections.firstWhere(
+        (s) => s.id == _selectedSectionId,
+        orElse: () => state.config!.sections.first,
+      );
+      return SectionView(
+        section: section,
+        wallState: state,
+        onBack: () => setState(() => _selectedSectionId = null),
+        onViewerTap: (viewerId) {
+          context.read<WallBloc>().add(SelectViewer(viewerId));
+          // Re-request focus for keyboard input after tile tap
+          _focusNode.requestFocus();
+        },
+      );
+    }
+
+    return WallOverview(
+      config: state.config!,
+      wallState: state,
+      onSectionTap: (sectionId) {
+        setState(() => _selectedSectionId = sectionId);
+      },
+    );
+  }
+
+  void _handleKeyEvent(KeyEvent event) {
+    if (event is! KeyDownEvent) return;
+
+    final bloc = _wallBloc;
+    if (bloc == null) return;
+
+    final state = bloc.state;
+    final key = event.logicalKey;
+
+    // Escape - go back or deselect
+    if (key == LogicalKeyboardKey.escape) {
+      if (state.selectedViewerId != null) {
+        bloc.add(const DeselectViewer());
+      } else if (_selectedSectionId != null) {
+        setState(() => _selectedSectionId = null);
+      }
+      return;
+    }
+
+    // Only handle camera input when a viewer is selected
+    if (state.selectedViewerId == null) return;
+
+    // Digit keys 0-9
+    if (key.keyId >= LogicalKeyboardKey.digit0.keyId &&
+        key.keyId <= LogicalKeyboardKey.digit9.keyId) {
+      final digit = key.keyId - LogicalKeyboardKey.digit0.keyId;
+      bloc.add(AddCameraDigit(digit));
+      return;
+    }
+
+    // Numpad digits
+    if (key.keyId >= LogicalKeyboardKey.numpad0.keyId &&
+        key.keyId <= LogicalKeyboardKey.numpad9.keyId) {
+      final digit = key.keyId - LogicalKeyboardKey.numpad0.keyId;
+      bloc.add(AddCameraDigit(digit));
+      return;
+    }
+
+    // Enter - execute CrossSwitch
+    if (key == LogicalKeyboardKey.enter ||
+        key == LogicalKeyboardKey.numpadEnter) {
+      if (state.canExecuteCrossSwitch) {
+        bloc.add(const ExecuteCrossSwitch());
+      }
+      return;
+    }
+
+    // Backspace - remove last digit
+    if (key == LogicalKeyboardKey.backspace) {
+      bloc.add(const BackspaceCameraDigit());
+      return;
+    }
+
+    // Delete - cancel edit
+    if (key == LogicalKeyboardKey.delete) {
+      bloc.add(const CancelCameraEdit());
+      return;
+    }
+
+    // Escape - cancel edit or deselect
+    if (key == LogicalKeyboardKey.escape) {
+      if (state.isEditing) {
+        bloc.add(const CancelCameraEdit());
+      } else {
+        bloc.add(const DeselectViewer());
+      }
+      return;
+    }
+
+    // F1-F3 for prefix selection
+    if (key == LogicalKeyboardKey.f1) {
+      bloc.add(const SetCameraPrefix(500));
+      return;
+    }
+    if (key == LogicalKeyboardKey.f2) {
+      bloc.add(const SetCameraPrefix(501));
+      return;
+    }
+    if (key == LogicalKeyboardKey.f3) {
+      bloc.add(const SetCameraPrefix(502));
+      return;
+    }
+  }
+}