fix(tui): canonicalize cwd after chdir

[Hona]

Fixes#16522
Fixes#16528
Fixes#16596

Use the same canonical cwd for the TUI thread and worker, including relative --project paths resolved from PWD.

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Before 1.2.21

• thread/TUI used: real dir /tmp/opencode-test-abc
• worker used: real dir /tmp/opencode-test-abc
• aligned: yes

In broken 1.2.21

• thread/TUI used: symlink dir /tmp/opencode-test-abc-link
• worker used: real dir /tmp/opencode-test-abc
• aligned: no

After this fix

• thread/TUI uses: real dir /tmp/opencode-test-abc
• worker uses: real dir /tmp/opencode-test-abc
• aligned: yes

For relative --project from a symlinked PWD

• it first resolves relative to the symlink-aware PWD
• then after chdir, it canonicalizes with process.cwd()
• final directory identity is again the real dir

[Copilot]

Pull request overview

This PR fixes TUI hangs/blank responses when launching OpenCode from symlinked directories by ensuring the TUI main thread and worker use the same canonical working directory (and still resolve relative --project paths from PWD).

Changes:

• Update TuiThreadCommand to chdir to the requested directory, then re-read process.cwd() and use that canonical value for Instance/TUI directory keys.
• Add a regression test covering the PWD-symlink scenario with and without a relative --project path.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
packages/opencode/src/cli/cmd/tui/thread.ts	Canonicalizes cwd after chdir so TUI thread and worker share the same directory key.
packages/opencode/test/cli/tui/thread.test.ts	Adds regression coverage for symlinked PWD causing mismatched directory keys.

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[Copilot]

The globalThis.Worker stub extends EventTarget without defining a constructor. Since TuiThreadCommand instantiates new Worker(file, { env: ... }), the default subclass constructor will forward those arguments to EventTarget, which typically throws because it expects no arguments. Add an explicit constructor(..._args: any[]) { super() } (or otherwise accept and ignore args) so the test doesn’t fail during Worker construction.

[brndnblck]

This fix completely broke MacOS and POSIX file systems if the working folder is a symlink. This needs to be reverted.

[brndnblck]

#16641