Add Windows support

[itzrnvr]

@## What

The CLI was entirely broken on Windows. src/colab_cli/console.py did unguarded module-level import termios / import tty, and since commands/execution.py imports connect_console from it at load time (cli.py:26), import colab_cli.cli raised ModuleNotFoundError: No module named termios on Windows. This killed every command (colab --help crashed) and made the entire pytest suite fail at collection (every test file does from colab_cli.cli import app). The README explicitly stated "Windows is not supported at this time."

Changes

• console.py — platform-guard the termios/tty imports (termios = tty = None on win32). connect_console now dispatches: POSIX keeps the existing termios/tty/SIGWINCH path; Windows uses a new ctypes raw-console path. The piped-stdin (isatty() == False) path is unchanged and cross-platform.
• _winconsole.py (new) — stdlib-ctypes Windows console helpers: a raw_mode() context manager that saves/restores CONIN$/CONOUT$ modes, enables ENABLE_VIRTUAL_TERMINAL_INPUT (disabling echo/line/processed input) and ENABLE_VIRTUAL_TERMINAL_PROCESSING on output, plus get_console_size() via GetConsoleScreenBufferInfo. No pywin32 dependency.
• console.py resize handling — Windows has no SIGWINCH; a daemon thread polls GetConsoleScreenBufferInfo every 0.25s and calls send_terminal_size(ws) on change.
• repl.py — defer PromptSession construction from ColabREPL.__init__ to run() (lazy, if self.session is None). prompt_toolkit's Win32Output calls GetConsoleScreenBufferInfo at PromptSession init and raised ctypes.ArgumentError under captured/non-tty stdout on Windows; constructing eagerly broke colab repl and 11 unit tests. Interactive use on a real Windows console is unaffected (run() builds the session against the real console).
• commands/files.py — edit() switched from NamedTemporaryFile(delete=True) (held an exclusive handle on Windows → open(path,"rb") for hashing and the editor raised PermissionError) to delete=False + close + manual os.unlink in finally.
• commands/automation.py — drivemount's open("/dev/tty") (FileNotFoundError on Windows) replaced with _read_line_from_controlling_tty(), which tries /dev/tty and falls back to sys.stdin.readline() on Windows.
• Tests — guarded POSIX termios/tty console tests with skipif(sys.platform == "win32"); added Windows console-mode set/restore tests (against the real CONIN$/CONOUT$); added cross-platform /dev/tty fallback tests; made _extract_command_names robust to both rounded (╭/╰) and square (┌/└) Rich help boxes and to wrapped description continuation lines (Windows renders square boxes and wraps VM/available onto their own lines).
• README.md / docs/02_execution_and_interactive.md — document Windows support and the Unix-only shebang (#!/usr/bin/env -S colab run / chmod +x) limitation.

Already Windows-handled (intentionally not touched)

spawn_keep_alive (DETACHED_PROCESS | CREATE_NEW_PROCESS_GROUP), state.py (filelock.ReadWriteLock, not fcntl), ~/.config/colab-cli paths (functional on Windows via ~ → C:\\Users\\<user>), common.kill_process (SIGTERM → TerminateProcess), auto_update.is_self_install_supported() (deliberately gated).

Verification (on Windows 11, Python 3.12.10)

• uv run python -c "import colab_cli.cli" → IMPORT OK (was: ModuleNotFoundError: No module named termios)
• uv run colab --help / version / repl --help / console --help / edit --help / drivemount --help / update → all run, exit 0
• uv run pytest tests/ -q → 237 passed, 1 skipped (was: 15 collection errors). The 1 skip is the POSIX termios-based console test on Windows.
• uv run ruff check src/colab_cli tests → clean
• _read_line_from_controlling_tty() verified on Windows: open("/dev/tty") raises OSError → falls back to sys.stdin.readline().
• _winconsole.raw_mode() verified against the real Windows console: input mode has ENABLE_VIRTUAL_TERMINAL_INPUT set and ENABLE_LINE_INPUT cleared mid-flight, restored on exit.

Not verified end-to-end

Interactive colab console / colab repl against a live Colab VM require OAuth + a billable VM allocation, which I can't provision autonomously. The raw-console ctypes path and command wiring are unit-tested and --help-verified; a live interactive session should be run by a reviewer on Windows Terminal to confirm end-to-end. Piped colab console/repl (non-VM) reach the websocket/prompt layer correctly.

Review with git diff main..windows-support.
@

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[itzrnvr]

Live end-to-end verification on Windows

Verified against real Colab VMs (free tier) on Windows 11, after uv tool install of this branch (0.6.1.dev3+g354692959):

Auth (oauth2 remote copy-paste flow) — colab sessions → URL printed, code pasted, token cached at ~/.config/colab-cli/token.json. ✅

CPU VM

• colab new -s wincpu → Session READY (~16s) ✅
• colab exec -s wincpu -f examples/_win_smoke_cpu.py → hello from colab-cli windows e2e / python: 3.12.13 | host os: Linux / cwd: /content ✅
• colab log -s wincpu -n 3 → recorded EXEC + console_started events ✅
• Piped echo "print(1+1)" | colab repl -s wincpu → 2 (lazy PromptSession fix) ✅
• Piped printf 'uname -a\r\n...' | colab console -s wincpu → connected via the Windows websocket TTY path, remote uname -a returned Linux e38600fadf01 6.6.122+ ... x86_64 GNU/Linux, tmux status bar rendered, clean close ✅
• colab stop -s wincpu → terminated ✅

Free-tier T4 GPU VM

• colab new -s wingpu --gpu T4 → Session READY (~21s) ✅
• colab exec -s wingpu -f examples/_win_smoke_gpu.py → torch: 2.11.0+cu128 / cuda available: True / device: Tesla T4 / matmul sum ok: True ✅
• colab stop -s wingpu → terminated ✅

Ephemeral job

• colab run --gpu T4 examples/_win_smoke_gpu.py → provisioned fresh T4 (run-e061d2), ran the script (CUDA True, Tesla T4, matmul ok), auto-tore-down ✅

Cleanup — colab sessions → No active sessions found on server. (no orphans) ✅

Not covered: the interactive (raw-TTY, human-at-keyboard) colab console/repl variants can'''t be automated, but the piped variants above exercise the same Windows websocket/PTY code paths against a live VM, and _winconsole.raw_mode() is unit-tested against the real Windows console (mode set/restore).