Implement project picker keyboard shortcut and enhance feature management

- Added a new keyboard shortcut 'P' to open the project picker dropdown.
- Implemented functionality to select projects using number keys, allowing users to quickly switch between projects.
- Updated the feature list to include a new feature for project selection via keyboard shortcuts.
- Removed obsolete coding_prompt.md and added initializer_prompt.md for better session management.
- Introduced context management for features, enabling reading, writing, and deleting context files.
- Updated package dependencies to include @radix-ui/react-checkbox for enhanced UI components.

This commit enhances user experience by streamlining project selection and improves the overall feature management process.

🤖 Generated with Claude Code

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

@@ -116,4 +116,5 @@ export const ACTION_SHORTCUTS: Record<string, string> = {
   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)
+  projectPicker: "P", // P for Project picker
 };