shared ToolCheck service, welcome status, logo doubled

ToolCheck kernel service checks ptyc/pql/tmux/git availability
once at boot, shared by status bar and welcome screen. Welcome
status line shows "application ok" in green or lists missing
tools in amber. Logo doubled to 144px. DialogHost moved inside
Expanded to fix blank workspace. Welcome maxWidth 850px, path
overflow fixed with Flexible.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lib/kernel/kernel.dart

@@ -46,4 +46,5 @@ export 'src/theme/palette.dart';
 export 'src/theme/resolver.dart';
 export 'src/theme/semantic.dart';
 export 'src/theme/tokens.dart';
+export 'src/tool_check.dart';
 export 'src/window_controls.dart';

lib/kernel/src/facade.dart

@@ -25,6 +25,7 @@ import 'package:clide/kernel/src/secrets.dart';
 import 'package:clide/kernel/src/settings.dart';
 import 'package:clide/kernel/src/theme/controller.dart';
 import 'package:clide/kernel/src/theme/loader.dart';
+import 'package:clide/kernel/src/tool_check.dart';
 import 'package:clide/kernel/src/tray.dart';
 import 'package:clide/kernel/src/window_controls.dart';
 import 'package:flutter/widgets.dart';
@@ -57,6 +58,7 @@ class KernelServices {
     required this.project,
     required this.extensions,
     required this.window,
+    required this.toolCheck,
   });
 
   final Logger log;
@@ -82,6 +84,7 @@ class KernelServices {
   final ProjectManager project;
   final ExtensionManager extensions;
   final WindowControls window;
+  final ToolCheck toolCheck;
 
   static Future<KernelServices> boot({
     required Directory appDir,
@@ -128,6 +131,7 @@ class KernelServices {
     final net = NetworkStatus();
     final focus = FocusTracker();
     final window = WindowControls();
+    final toolCheck = ToolCheck();
     final project = ProjectManager(
       log: log,
       events: events,
@@ -192,6 +196,7 @@ class KernelServices {
       project: project,
       extensions: extensions,
       window: window,
+      toolCheck: toolCheck,
     );
   }
 

lib/kernel/src/tool_check.dart

@@ -0,0 +1,41 @@
+import 'dart:io';
+
+import 'package:flutter/foundation.dart';
+
+class ToolCheck extends ChangeNotifier {
+  bool ptycOk = false;
+  bool pqlOk = false;
+  bool tmuxOk = false;
+  bool gitOk = false;
+  bool checked = false;
+
+  bool get allOk => ptycOk && pqlOk && tmuxOk && gitOk;
+
+  List<String> get errors => [
+        if (!ptycOk) 'ptyc not found',
+        if (!pqlOk) 'pql not found',
+        if (!tmuxOk) 'tmux not found',
+        if (!gitOk) 'git not found',
+      ];
+
+  Future<void> check() async {
+    final cwd = Directory.current.path;
+    ptycOk = File('$cwd/native/linux-x64/ptyc').existsSync() ||
+        File('$cwd/ptyc/bin/ptyc').existsSync() ||
+        await _which('ptyc');
+    pqlOk = await _which('pql');
+    tmuxOk = await _which('tmux');
+    gitOk = await _which('git');
+    checked = true;
+    notifyListeners();
+  }
+
+  static Future<bool> _which(String name) async {
+    try {
+      final r = await Process.run('which', [name]);
+      return r.exitCode == 0;
+    } catch (_) {
+      return false;
+    }
+  }
+}