fix(tool): detect repo root from a linked worktree in build_skill_assets

[dipsy]

Problem

_findRepoRoot() in mcp_server_dart/tool/build_skill_assets.dart walks up from the current directory looking for a .git directory. In a linked worktree (git worktree add) — and in a submodule checkout — .git is a file holding a gitdir: pointer, so the walk runs past the repo root and the tool aborts:

Unhandled exception:
Bad state: Not in a git repo
#0      _findRepoRoot (.../mcp_server_dart/tool/build_skill_assets.dart:138:3)
#1      main (.../mcp_server_dart/tool/build_skill_assets.dart:30:20)
make: *** [sync-skills] Error 255

sync-skills is a prerequisite of compile, so make compile cannot run from a worktree at all. That is a normal setup when validating a PR branch side by side with a working checkout.

Change

Accept both shapes of the marker — a .git directory or a .git file. Plain clones still match the directory check first, so their behaviour is unchanged.

Verification

From a linked worktree, all previously failing paths now succeed and regenerate skill_assets.g.dart byte-identically to the committed file:

• make sync-skills in mcp_server_dart/ — the exact command that failed above;
• dart run mcp_server_dart/tool/build_skill_assets.dart from the worktree root and from a nested package directory;
• bash tool/contracts/check_skill_assets_drift.sh → skill_assets.g.dart in sync with plugin/;
• git status after the runs shows no drift beyond the tool file itself.

Summary by CodeRabbit

• Bug Fixes
  • Improved repository detection across standard checkouts, linked worktrees, and submodules.
  • Build asset discovery now works when Git metadata is represented by either a directory or a file.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 31821852-71cd-4fca-962a-4a761553d620

📥 Commits

Reviewing files that changed from the base of the PR and between 6975f88 and 3ea5433.

📒 Files selected for processing (1)

• mcp_server_dart/tool/build_skill_assets.dart

---

📝 Walkthrough

Walkthrough

Changes

Repository root detection

Layer / File(s)	Summary
Support file-based Git markers mcp_server_dart/tool/build_skill_assets.dart	_findRepoRoot() now recognizes both .git directories and .git files for standard clones, linked worktrees, and submodules.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Suggested reviewers: arenukvern

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly describes the main change: improving repo-root detection for build_skill_assets in linked worktrees.
Description check	✅ Passed	The description covers the problem, change, and verification, but it does not follow the template's exact Summary/Validation/Checklist/Notes headings.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}