fix(hub): kill the whole child-process tree on Windows

[antfubot]

Description

Reworks #404 (from @zahidzorbaz, whose fork branch we can't push to) so the Windows tree kill goes through tinyexec instead of a hand-rolled node:child_process spawn.

On Windows, stopping a startChildProcess() session left the real program running: tinyexec runs anything that isn't a .exe/.com (including node_modules/.bin/*.cmd shims) through cmd.exe /d /s /c, so the pid the host holds is the wrapper's, and cp.kill() doesn't reach descendants.

This PR keeps the approach and behaviour of #404 unchanged:

• killProcessTree() in host-terminals.ts: on Windows it runs taskkill /pid <pid> /T /F and falls back to cp.kill(); elsewhere it is cp.kill() as before.
• Used in terminate(), restart() and the stream's cancel(); restart() waits for the old tree to exit so the new run can take the same ports.
• Host-initiated stops report status: 'stopped', exitCode: undefined, killed: true on every platform.

What changed vs #404: taskkill is spawned with tinyexec's exec (already a dependency and already used in this file) rather than raw spawn plus manual promise/event wiring — tinyexec itself has no built-in tree kill (kill() is plain child.kill), so taskkill stays, but the wrapper shrinks from ~20 lines to ~10.

Linked Issues

Fixes #402
Supersedes #404

Additional context

Tests are carried over verbatim from #404: a describe.runIf(win32) block exercising a real .cmd shim (skipped on Linux/macOS CI). On Linux: pnpm lint, pnpm knip, pnpm test, pnpm typecheck, pnpm build all pass.

Created with the help of an agent, based on the original work in #404.

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🟢 +0 new · 🟠 ~1 changed · 🔴 -0 removed · 1 flow · 3 files · commit dbc8449

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1 Skipped Deployment

Project	Deployment	Actions	Updated
devframe	Skipped		Sep 25, 2026 12:46am UTC