fix(ui): keep settings sidebar open, center content, and fix worktree refresh (#1058)

* 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

---------

Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/src/components/views/SettingsWindow.tsx

@@ -41,7 +41,7 @@ export const SettingsWindow: React.FC<SettingsWindowProps> = ({ open, onOpenChan
           aria-describedby={descriptionId}
           className={cn(
             'fixed z-50 top-[50%] left-[50%] translate-x-[-50%] translate-y-[-50%]',
-            'w-[90vw] max-w-[960px] h-[85vh] max-h-[900px]',
+            'w-[90vw] max-w-[1200px] h-[85vh] max-h-[900px]',
             'rounded-xl border shadow-none overflow-hidden',
             'bg-background'
           )}