feat(app): pin projects to the top of the sidebar

[Gabriel-Kahen]

Issue for this PR

Closes #

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

This adds project pinning to the left sidebar so frequently used projects stay anchored above the rest of the open project list. The pin state is persisted with the existing stored sidebar project state, the rail now keeps pinned projects grouped first, and both the collapsed rail menu and expanded project menu expose matching pin and unpin actions.

The UI changes are intentionally small so they fit the current sidebar: pinned projects get a subtle pin badge in the rail and a divider appears between pinned and unpinned groups. Dragging still works within each group, and cross-group dragging is blocked so the pinned section remains stable unless the user explicitly pins or unpins a project.

How did you verify your code works?

I checked the failing CI typecheck log and fixed the pinned property being dropped in packages/app/src/context/layout.tsx during project enrichment. I could not run local Bun-based checks in this environment because bun is not installed on the machine path here.

Screenshots / recordings

UI change in the left sidebar:

• project context menus now include Pin project / Unpin project
• pinned projects show a small pin badge in the collapsed rail
• pinned projects stay grouped at the top with a divider below them

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[github-actions]

This PR doesn't fully meet our contributing guidelines and PR template.

What needs to be fixed:

• Not all checklist items are checked. Please confirm you have tested locally and have not included unrelated changes.

Please edit this PR description to address the above within 2 hours, or it will be automatically closed.

If you believe this was flagged incorrectly, please let a maintainer know.

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Potential Duplicate PRs Found

The following PRs are related to project pinning features in the sidebar and may be duplicates:

1. feat(app): add project pinning to sidebar menu (feat(app): add project pinning to sidebar menu #17999)

   • feat(app): add project pinning to sidebar menu #17999
   • Directly related: adds pin functionality to project sidebar menu

2. feat(app): add pinned workspaces in sidebar (feat(app): add pinned workspaces in sidebar #16068)

   • feat(app): add pinned workspaces in sidebar #16068
   • Related feature: implements pinning for workspaces in sidebar

3. feat(app): add dynamic sidebar sorting for active projects and sessions (feat(app): add dynamic sidebar sorting for active projects and sessions #11758)

   • feat(app): add dynamic sidebar sorting for active projects and sessions #11758
   • Related: manages sidebar organization for projects/sessions

4. feat: redesign sidebar with Codex-style unified view (feat: redesign sidebar with Codex-style unified view #20242)

   • feat: redesign sidebar with Codex-style unified view #20242
   • May contain overlapping sidebar UI changes

Please check these PRs (especially #17999) to verify if PR #21382 is addressing the same feature or if there are conflicting changes.