feat(app): Motion drawer for sidebar expand/collapse

[oxwen11]

Summary

• Port of pie#72: desktop sidebar toggle springs as a push drawer (width MotionValue, x = width - expanded) instead of squashing the rail.
• Card heading uses Motion layout projection so collapsed chrome does not snap. LazyMotion + m (domMax) load the features.
• Vibest has no ShellSidebarToggle or collapsed BrandMark in the card header — those pie surfaces were not invented here. Mobile still uses the Sheet overlay.

Test plan

• Toggle: rail slides off-screen (data-state=closed, inert, panel width ~0); chat heading toggle reopens it
• Drag the sidebar separator: width snaps (256 → 336), no spring
• Mobile viewport: no desktop drawer; Toggle Sidebar opens the Sheet dialog
• Reduced-motion: collapse/expand jumps without the spring

Made with Cursor

[github-actions]

React Doctor found 1 issue in 1 file · 1 warning · score 92 / 100 (Great) · full project

1 warning

src/features/chat/runtime/client-prompt-queue.ts

• ⚠️ L0 unused-file

_{Reviewed by React Doctor for commit aa0795d. See inline comments for fixes.}