* fix(app): route workspace actions semantically
Separate Explorer visibility from view navigation, and give composer changes and pull request opens semantic routing owners. Unify diff destinations, keep compact PR navigation in Explorer, and derive maximize availability from visible workspace panes.
* test(app): cover composer changes routing
Update the browser journey for the Explorer-first composer action, then assert the second press follows the shared diff destination.
* fix(app): preserve desktop layout in half-screen windows
Treat native window controls as physical corner obstructions instead of deriving clearance from compact layout state. Keep 751px windows in desktop mode while preserving usable content when persisted sidebars are wide.
* fix(app): retain sidebar width across window resizes
* fix(app): yield app sidebar to narrow settings
* test(app): wait for mobile sidebar motion to settle
* fix(app): yield navigation to narrow workspace explorer
* fix(app): mark sidebar sizing helpers as worklets
* fix(app): hide app navigation when space is constrained