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

[FXschwartz]

Fixes three Windows only issues:

1. Win32AnsiStdin._eventLoop blocks the Dart isolate

ReadConsoleInputW was called with no timeout, blocking the OS thread until input arrived. While blocked, no timers, futures, signal handlers, or render frames fire. The await Future.delayed(Duration.zero) at the top of the loop only yields between blocking calls.

Fix: call WaitForSingleObject(handle, 16) first; only call ReadConsoleInputW when the handle is signaled. Caps FFI time at ~16ms.

2. Ctrl+C path inactive on Windows

enableRawMode calls stdin.lineMode = false, which on Windows clears ENABLE_PROCESSED_INPUT. Without that flag, Windows doesn't generate CTRL_C_EVENT, so Dart's ProcessSignal.sigint.watch() doesn't fire.

Fix: re-assert ENABLE_PROCESSED_INPUT in startEventLoop(). With ENABLE_LINE_INPUT still off, only Ctrl+C is intercepted; other Ctrl+letter combos still arrive as key events.

3. getProjectDirectory() doesn't terminate on Windows drive roots

if (newParent == parent) is identity equality on Directory (.parent returns a new instance each call, so this never matches). if (newParent.path == '/') is POSIX-only. From a directory with no pubspec.yaml ancestor on Windows, the walk iterates on C:\ indefinitely. Called synchronously from LogServer._writePortFile(), which is awaited in _runApp before TerminalBinding.initialize(), so runApp itself doesn't progress.

Fix: compare paths (newParent.path == parent.path), and fall back to Directory.current.path instead of throwing.

I also added new unit tests in test/utils/nocterm_paths_test.dart cover getProjectDirectory's three behaviors

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Improves path discovery behavior and Windows console input handling by making project root detection terminate safely across platforms and keeping the Windows stdin event loop responsive (including Ctrl+C/SIGINT behavior).

Changes:

• Added unit tests for getProjectDirectory() behavior with/without pubspec.yaml.
• Updated getProjectDirectory() to terminate by comparing paths (works for Windows drive roots) and return cwd when no ancestor contains pubspec.yaml.
• Updated Windows stdin backend to re-enable ENABLE_PROCESSED_INPUT and poll input availability with WaitForSingleObject to avoid starving the Dart event loop.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
test/utils/nocterm_paths_test.dart	Adds tests validating getProjectDirectory() ancestor walking behavior.
lib/src/utils/nocterm_paths.dart	Fixes termination condition when walking to filesystem roots; changes fallback behavior.
lib/src/backend/win32_ansi_stdin.dart	Makes Windows stdin loop responsive + preserves Ctrl+C generation by adjusting console mode and using a bounded wait.

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[FXschwartz]

@Norbert515 Sorry for the ping, I'm sure you are busy but when you get a chance could you take a look at this PR? No rush!