feat(web): add file tree expansion toggle

[StiensWout]

Summary

• add one compact, state-aware expand/collapse control to the workspace file explorer
• keep the control synchronized with individual directory expansion state
• apply bulk expansion in one tree-model reset instead of emitting once per folder
• disable the bulk action while file search owns temporary expansion state
• avoid resets for empty trees and folders already in the requested state

Rationale

Large workspace trees currently require closing directories one at a time. The state-aware control provides a small, predictable way to reset or inspect the full tree without changing existing per-directory or initial-expansion behavior.

The bulk operation rebuilds the existing path set with the requested expansion set in one model emission, keeping the operation linear for large indexed workspaces. A 2,000-directory regression test asserts one emission and at most two item reads per directory across the precheck and subscribed state update.

Closes #4227.

Validation

• vp test run src/components/files/fileTreeExpansion.test.ts (9 tests passed)
• vp lint --report-unused-disable-directives apps/web/src/components/files/FileBrowserPanel.tsx apps/web/src/components/files/fileTreeExpansion.ts apps/web/src/components/files/fileTreeExpansion.test.ts
• vp run --filter @t3tools/web typecheck
• vp fmt apps/web/src/components/files/FileBrowserPanel.tsx apps/web/src/components/files/fileTreeExpansion.ts apps/web/src/components/files/fileTreeExpansion.test.ts --check
• git diff --check
• integrated web verification: paired successfully, confirmed one toggle, and exercised Collapse → Expand → Collapse on a populated workspace tree

Image

---

Note

Low Risk
UI-only file explorer behavior with well-tested expansion helpers; no auth, data, or API surface changes.

Overview
Adds Collapse all and Expand all toolbar buttons to the workspace file explorer, wired to a new fileTreeExpansion helper that tracks expansion state (expanded, collapsed, mixed, searching, empty) and applies bulk changes via a single resetPaths with initialExpandedPaths instead of per-folder toggles.

Button enablement follows that snapshot: both are off while search is open or the tree is empty; collapse/expand only when the action would change anything. Path refreshes now reset with initialExpansion: "closed" plus explicit depth-one initialExpandedPaths so default open folders match the old initialExpansion: 1 behavior while bulk operations stay batched.

Unit tests cover path normalization, parity with the old initial expansion, no-ops when already fully expanded/collapsed, search guardrails, and a 2k-folder regression for a single model emission.

^{Reviewed by Cursor Bugbot for commit e487f19. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Add expand/collapse all folders toggle to file browser panel

• Adds a toggle button in the FileBrowserPanel header that expands or collapses all directories at once, using new utilities in fileTreeExpansion.ts.
• The button renders ChevronsUpDown or ChevronsDownUp based on current expansion state, which is tracked via useSyncExternalStore and classified as collapsed, expanded, mixed, empty, or searching.
• The button is disabled when the tree is empty or a search is active; clicking calls setAllDirectoriesExpanded, which batch-resets expansion via model.resetPaths.
• Behavioral Change: FileTree initial expansion switches from a numeric depth (1) to "closed" with depth-one paths supplied via initialExpandedPaths on reset, preserving the same visual default.

^{Macroscope summarized 1bd7545.}

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: aafa1717-b3f1-44b2-8c4a-f0c3c093816d

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

✨ 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.}

[cursor]

Cursor Bugbot has reviewed your changes using high effort and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit e8a976f. Configure here.}

[macroscopeapp]

Approvability

Verdict: Needs human review

This PR adds a new user-facing feature (expand/collapse all folders toggle) to the file browser. While well-tested and self-contained, new user-facing functionality warrants human review to ensure the UX matches expectations.

^{You can customize Macroscope's approvability policy. Learn more.}