Support linked worktrees and submodules, where .git is a file

[EsmeYi]

Problem

In a linked worktree or a submodule, .git is a file (gitdir: ...), not a directory, so every <repo>/.git/tracybot/... path breaks. Found while reviewing #145; this is already broken on main, not a regression from that PR.

Reproduced on real repos (plain repo vs linked worktree vs submodule), running the real init.py and then a real git commit through the installed hooks:

	init.py before	init.py after
plain repo	ok	ok
linked worktree	NotADirectoryError	ok, commit creates a snapshot
submodule	NotADirectoryError: no config, no hooks, no snapshots at all	ok, commit creates a snapshot

Same assumption elsewhere: the three agent plugins couldn't find the config (so nothing was recorded), and writing the Research Mode consent file (repoConsent.ts) threw ENOTDIR, e.g. clicking "I agree to share my data" in a worktree.

Fix

Resolve the real location instead of assuming .git/. Everything Tracybot keeps under the git dir goes in the common git dir. That is where the hooks are installed and where pre-commit.py already reads the config from (the parent of the hooks dir), so init and consent are per repository, not per worktree.

• init.py, post-fetch.py: git rev-parse --git-common-dir
• opencode / claude-code / codex plugins and repoConsent.ts: new resolveGitDir() that follows the .git file and the worktree's commondir pointer. No git process needed. vscode-extension/src/gitDir.ts is the reusable one.

Related: #145

tracyInitCheck.ts (the extension's check for "is this repo initialized?") now goes through resolveGitDir too, otherwise init would succeed in a worktree while the extension kept thinking it was uninitialized and re-ran it on every activation. #145 rewrites that code and moves it into a new initState.ts, so whichever of the two merges second needs a small conflict resolution, and initState.ts must use resolveGitDir (from src/gitDir.ts) as well. Use the common dir, not git rev-parse --git-path: that gives a per-worktree path that the hooks don't read.

post-fetch.py isn't a hook name git actually runs, so that change is for consistency only.

Testing

• vscode-extension unit tests: 66/66 (new gitDir.test.ts with a real linked worktree and submodule, plus a consent round-trip from a worktree)
• claude-code-plugin and codex-plugin bun test: 12/12 each (new tests for resolveTracyPath in a worktree and a submodule)
• Confirmed the new worktree/submodule tests fail without the fix (consent test in the extension; 2 tests in each plugin)
• All four packages type-check, plugins build
• End-to-end init.py + real hooked commit in a plain repo, linked worktree and submodule, before and after (table above)
• The opencode plugin has no test harness; it uses the same resolver code and type-checks/builds, but I did not exercise it against a live OpenCode session

🤖 Generated with Claude Code