feat(sidebar): add folder context menu and empty group placeholders

[MattPua]

Problem

Folders without tasks were invisible in by-project mode, and there was no way to add/remove folders from the sidebar.

Needed a way to quickly open tasks with a specific project because i often forget to change it when starting a new task via the dropdown.

Changes

CleanShot.2026-07-03.at.13.40.16.mp4

• Empty folders now show in by-project mode with a "No agents yet" placeholder
• Right-click a folder header to remove it or open in external app
• Add folder button in the tasks header opens the OS directory picker
• Extracted folderGroupId so folder↔group matching logic lives in one place

How did you test this?

Manual testing in the app.

Automatic notifications

• Publish to changelog?
• Alert Sales and Marketing teams?

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[github-actions]

React Doctor found no issues in the changed files. 🎉

_{Reviewed by React Doctor for commit ab01fc1.}

[greptile-apps]

Comments Outside Diff (1)

1. packages/core/src/sidebar/groupTasks.ts, line 100-106 (link)

   Disambiguation silently no-ops for empty folder groups

   The organization is sourced from group.tasks[0]?.repository?.organization, which is always undefined for the new empty placeholder groups (tasks: []). If a user has two workspace folders with the same display name but no active tasks in either, both groups render with identical labels and the user has no way to tell them apart. The same gap applies to non-remote folders in general (where getRepositoryInfo never sets organization), but those groups at least had tasks before; the empty-group feature makes the collision much easier to hit.

   Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

_{Reviews (1): Last reviewed commit: "feat(sidebar): add folder context menu a..." | Re-trigger Greptile}

[greptile-apps]

_{Reviews (2): Last reviewed commit: "fix(sidebar): say "No tasks yet" instead..." | Re-trigger Greptile}