Add keyboard shortcut 'W' for creating new agent session

- Added newSession shortcut to ACTION_SHORTCUTS in use-keyboard-shortcuts.ts
- Updated SessionManager to expose quick create function via ref
- Updated AgentView to register the shortcut and trigger new session creation
- Display shortcut key indicator (W) on the New session button
- Updated feature_list.json to mark feature as verified

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/src/hooks/use-keyboard-shortcuts.ts

@@ -100,10 +100,20 @@ export const NAV_SHORTCUTS: Record<string, string> = {
   settings: "S", // S for Settings
 };
 
+/**
+ * Shortcut definitions for UI controls
+ */
+export const UI_SHORTCUTS: Record<string, string> = {
+  toggleSidebar: "`", // Backtick to toggle sidebar
+};
+
 /**
  * Shortcut definitions for add buttons
  */
 export const ACTION_SHORTCUTS: Record<string, string> = {
   addFeature: "N", // N for New feature
   addContextFile: "F", // F for File (add context file)
+  startNext: "Q", // Q for Queue (start next features from backlog)
+  newSession: "W", // W for new session (in agent view)
+  openProject: "O", // O for Open project (navigate to welcome view)
 };