Initial commit: Antigravity dev container with Happy Coder

Add containerized GUI development environment featuring:
- Antigravity IDE (VSCode) accessible via web browser
- Happy Coder AI assistant integration
- Automatic GitHub repository cloning on startup
- Persistent user home directory (ReadWriteMany PVC)
- Secure non-root execution as user claude (UID 1000)

Components:
- Dockerfile based on jlesage/baseimage-gui
- Startup scripts for repo initialization and app launch
- Kubernetes manifests (StatefulSet, ConfigMap, Secrets)
- Makefile for build and deployment automation
- Comprehensive documentation

Features:
- Web-based VNC interface (port 5800)
- GitHub token authentication for private repos
- Happy Coder runs as background service in workspace
- CephFS storage for persistent home directory
- Configurable display resolution and security

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

k8s/configmap.yaml

@@ -0,0 +1,9 @@
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: antigravity-config
+data:
+  # GitHub repository to clone on startup
+  # Example: "https://github.com/username/repository"
+  github-repo: ""