* fix(ui): keep settings sidebar open, center content, and fix worktree refresh
- Prevent settings nav from collapsing on split pages (Magic Prompts, Agents, etc.)
- Center settings content with max-w-3xl for better layout on wide screens
- Widen settings window from 960px to 1200px max-width
- Fix source branch dropdown overflow with max-height and scrolling
- Add worktreeRefreshNonce to trigger immediate sidebar refresh after worktree creation
* ref(ui): address Greptile review — remove dead isNavCollapsed code and split worktree effect
- Remove isNavCollapsed variable and all dead branches (resize handle, renderSettingsNav param, SETTINGS_NAV_RAIL_WIDTH)
- Split SessionSidebar effect so worktreeRefreshNonce only triggers discoverWorktrees, not refreshGlobalSessions
- Both type-check and lint pass
* fix(ui): refine settings and worktree dropdown behavior
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Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>
