feat: initial VS Code extension for OpenClaude

Introduce OpenClaude as a first-class VS Code extension with:

- Built-in Control Center sidebar for seamless workflow integration
- Terminal-first design with authentic monospace UI and ASCII styling
- Quick-launch buttons for OpenClaude terminal, repository access, and command palette
- Status display showing runtime and OpenAI shim configuration
- Dark theme optimized for focus and extended development sessions
- Proper extension manifest with activation events and contribution points
- Debug configuration for local development

This extension provides developers with direct access to OpenClaude
without leaving VS Code, enabling a tighter integration with the editor.

vscode-extension/openclaude-vscode/package.json

@@ -12,6 +12,7 @@
     "Other"
   ],
   "activationEvents": [
+    "onStartupFinished",
     "onCommand:openclaude.start",
     "onCommand:openclaude.openDocs",
     "onCommand:openclaude.openControlCenter",