fix(skills): harden plugin root resolution across install modes

[0xnayuta]

Summary

This PR improves plugin root resolution robustness for /understand and /understand-dashboard across different installation modes and hosts.

What changed

• Prioritize CLAUDE_PLUGIN_ROOT as the first plugin-root candidate (runtime-provided root should win)
• Keep existing universal symlink fallback: ~/.understand-anything-plugin
• Keep self-relative fallback from ~/.agents/skills/... real path
• Add Copilot personal-skills fallback from ~/.copilot/skills/... real path
• Add common clone-path fallbacks:
  • ~/.codex/understand-anything/understand-anything-plugin
  • ~/.opencode/understand-anything/understand-anything-plugin
  • ~/.pi/understand-anything/understand-anything-plugin
  • ~/understand-anything/understand-anything-plugin
• Align root-resolution behavior between understand and understand-dashboard
• Improve error diagnostics by listing all checked candidates in failure output

Why

/understand could fail with “Cannot find the understand-anything plugin root” in valid installs where:

• ~/.understand-anything-plugin is absent, and
• ~/.agents/skills/... is unavailable/unresolvable, while
• a valid runtime root is available (e.g. CLAUDE_PLUGIN_ROOT).

This could also cause inconsistent behavior between skills (/understand vs /understand-dashboard) and potential version mismatch when multiple roots exist.

Impact

• Fixes root resolution regressions in Claude native setups
• Improves compatibility for Copilot personal-skills and common clone-based installs
• Reduces ambiguity by using consistent priority and clearer error messages

Commits in this PR branch

• a2071fb fix(pi): resolve understand plugin root via symlink-safe logic
• 6a071b5 chore(pi): improve plugin root error message
• d9250d7 fix(skills): harden plugin root resolution across install modes

[Copilot]

Pull request overview

Updates the /understand skill’s pre-flight instructions to resolve the Understand Anything plugin root in a symlink-safe way (targeting Pi installs where skills are exposed via symlinks), ensuring pnpm commands run in the correct workspace directory.

Changes:

• Adds symlink-safe resolution for the skill path via realpath/readlink -f to derive a self-relative plugin root.
• Prefers the universal plugin-root symlink ~/.understand-anything-plugin when present, with fallback to the resolved real checkout path.
• Validates candidates by checking for package.json and pnpm-workspace.yaml before running build steps.

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[Lum1104]

Thanks for the contribution!

[Lum1104]

@codex review this

[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: 6a071b5abd

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[Lum1104]

@codex review this

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Another round soon, please!

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".