fix(windows): non-blocking input loop, restore Ctrl+C, drive-root path walk

lib/src/backend/win32_ansi_stdin.dart

@@ -54,21 +54,39 @@ class Win32AnsiStdin extends Stream<List<int>> implements Stdin {
   void startEventLoop() {
     if (_running) return;
     _running = true;
+    // Dart's stdin.lineMode = false clears ENABLE_PROCESSED_INPUT, which is
+    // what makes Windows generate SIGINT for Ctrl+C.
+    _ensureProcessedInput();
     _eventLoop();
   }
 
+  void _ensureProcessedInput() {
+    final modePtr = calloc<Uint32>();
+    try {
+      if (_getConsoleMode(_inputHandle, modePtr) != 0) {
+        _setConsoleMode(_inputHandle, modePtr.value | _enableProcessedInput);
+      }
+    } finally {
+      calloc.free(modePtr);
+    }
+  }
+
   Future<void> _eventLoop() async {
     final pInputRecord = calloc<_InputRecord>();
     final pEventsRead = calloc<Uint32>();
 
     try {
       while (_running) {
-        // Yield to Dart event loop
         await Future.delayed(Duration.zero);
+        if (!_running) break;
 
+        // Bounded wait keeps the Dart event loop responsive. Without this,
+        // ReadConsoleInputW parks the isolate until the next keystroke,
+        // starving timers and signal handlers.
+        final waitResult = _waitForSingleObject(_inputHandle, _pollIntervalMs);
         if (!_running) break;
+        if (waitResult != _waitObject0) continue;
 
-        // Read one input event
         final result =
             _readConsoleInputW(_inputHandle, pInputRecord, 1, pEventsRead);
         if (result != 0 && pEventsRead.value > 0) {
@@ -377,10 +395,17 @@ class Win32AnsiStdin extends Stream<List<int>> implements Stdin {
 
 // Windows API Constants
 const int _stdInputHandle = -10;
+const int _enableProcessedInput = 0x0001;
 const int _enableMouseInput = 0x0010;
 const int _enableExtendedFlags = 0x0080;
 const int _enableQuickEditMode = 0x0040;
 
+// WaitForSingleObject return value: object is signaled.
+const int _waitObject0 = 0x00000000;
+
+// 16ms poll keeps the input loop responsive.
+const int _pollIntervalMs = 16;
+
 // Event types
 const int _keyEvent = 0x0001;
 const int _mouseEvent = 0x0002;
@@ -494,6 +519,11 @@ typedef _ReadConsoleInputDart = int Function(
     int nLength,
     Pointer<Uint32> lpNumberOfEventsRead);
 
+typedef _WaitForSingleObjectNative = Uint32 Function(
+    IntPtr hHandle, Uint32 dwMilliseconds);
+typedef _WaitForSingleObjectDart = int Function(
+    int hHandle, int dwMilliseconds);
+
 final _kernel32 = DynamicLibrary.open('kernel32.dll');
 
 final _getStdHandle = _kernel32
@@ -510,3 +540,7 @@ final _setConsoleMode =
 final _readConsoleInputW =
     _kernel32.lookupFunction<_ReadConsoleInputNative, _ReadConsoleInputDart>(
         'ReadConsoleInputW');
+
+final _waitForSingleObject = _kernel32.lookupFunction<
+    _WaitForSingleObjectNative,
+    _WaitForSingleObjectDart>('WaitForSingleObject');

lib/src/utils/nocterm_paths.dart

@@ -28,22 +28,16 @@ String getNoctermDirectory() {
 }
 
 String getProjectDirectory() {
+  final start = Directory.current.path;
   var parent = Directory.current;
   while (true) {
-    final newParent = parent.parent;
-
-    if (newParent == parent) {
-      throw StateError('Could not determine project directory');
-    }
-
     final pubspec = File(p.join(parent.path, 'pubspec.yaml'));
-    if (pubspec.existsSync()) {
-      return parent.path;
-    }
-    if (newParent.path == '/') {
-      return '/';
-    }
+    if (pubspec.existsSync()) return parent.path;
 
+    final newParent = parent.parent;
+    // Compare paths, not Directory identity — terminates at Windows drive
+    // roots where parent.parent returns the same path.
+    if (newParent.path == parent.path) return start;
     parent = newParent;
   }
 }

test/utils/nocterm_paths_test.dart

@@ -0,0 +1,48 @@
+import 'dart:io';
+
+import 'package:nocterm/src/utils/nocterm_paths.dart';
+import 'package:path/path.dart' as p;
+import 'package:test/test.dart';
+
+void main() {
+  group('getProjectDirectory', () {
+    late Directory tempRoot;
+    late Directory previousCwd;
+
+    setUp(() {
+      previousCwd = Directory.current;
+      tempRoot = Directory.systemTemp.createTempSync('nocterm_paths_test_');
+    });
+
+    tearDown(() {
+      Directory.current = previousCwd;
+      if (tempRoot.existsSync()) tempRoot.deleteSync(recursive: true);
+    });
+
+    test('returns the closest ancestor containing pubspec.yaml', () {
+      final project = Directory(p.join(tempRoot.path, 'project'))..createSync();
+      File(p.join(project.path, 'pubspec.yaml')).writeAsStringSync('name: x');
+      final nested = Directory(p.join(project.path, 'a', 'b'))
+        ..createSync(recursive: true);
+      Directory.current = nested;
+
+      expect(getProjectDirectory(), equals(project.path));
+    });
+
+    test('returns cwd when no pubspec.yaml ancestor exists', () {
+      final dir = Directory(p.join(tempRoot.path, 'a', 'b', 'c'))
+        ..createSync(recursive: true);
+      Directory.current = dir;
+
+      expect(getProjectDirectory(), equals(dir.path));
+    });
+
+    test('terminates when walking past the filesystem root', () {
+      final dir = Directory(p.join(tempRoot.path, 'deep', 'no', 'project'))
+        ..createSync(recursive: true);
+      Directory.current = dir;
+
+      expect(getProjectDirectory(), equals(dir.path));
+    });
+  });
+}