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/package-lock.json

@@ -12,6 +12,7 @@
         "@dnd-kit/core": "^6.3.1",
         "@dnd-kit/sortable": "^10.0.0",
         "@dnd-kit/utilities": "^3.2.2",
+        "@radix-ui/react-checkbox": "^1.3.3",
         "@radix-ui/react-dialog": "^1.1.15",
         "@radix-ui/react-dropdown-menu": "^2.1.16",
         "@radix-ui/react-label": "^2.1.8",
@@ -2559,6 +2560,36 @@
         }
       }
     },
+    "node_modules/@radix-ui/react-checkbox": {
+      "version": "1.3.3",
+      "resolved": "https://registry.npmjs.org/@radix-ui/react-checkbox/-/react-checkbox-1.3.3.tgz",
+      "integrity": "sha512-wBbpv+NQftHDdG86Qc0pIyXk5IR3tM8Vd0nWLKDcX8nNn4nXFOFwsKuqw2okA/1D/mpaAkmuyndrPJTYDNZtFw==",
+      "license": "MIT",
+      "dependencies": {
+        "@radix-ui/primitive": "1.1.3",
+        "@radix-ui/react-compose-refs": "1.1.2",
+        "@radix-ui/react-context": "1.1.2",
+        "@radix-ui/react-presence": "1.1.5",
+        "@radix-ui/react-primitive": "2.1.3",
+        "@radix-ui/react-use-controllable-state": "1.2.2",
+        "@radix-ui/react-use-previous": "1.1.1",
+        "@radix-ui/react-use-size": "1.1.1"
+      },
+      "peerDependencies": {
+        "@types/react": "*",
+        "@types/react-dom": "*",
+        "react": "^16.8 || ^17.0 || ^18.0 || ^19.0 || ^19.0.0-rc",
+        "react-dom": "^16.8 || ^17.0 || ^18.0 || ^19.0 || ^19.0.0-rc"
+      },
+      "peerDependenciesMeta": {
+        "@types/react": {
+          "optional": true
+        },
+        "@types/react-dom": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/@radix-ui/react-collection": {
       "version": "1.1.7",
       "resolved": "https://registry.npmjs.org/@radix-ui/react-collection/-/react-collection-1.1.7.tgz",