feat: Claude Web UI POC with streaming and tool visualization

Initial implementation of a web-based Claude Code interface with:

Backend (Node.js + Express + WebSocket):
- Claude CLI spawning with JSON stream mode
- Session management with resume support (--continue flag)
- Session history API endpoint
- Real-time WebSocket communication
- --include-partial-messages for live streaming

Frontend (React + Vite + Tailwind):
- Modern dark theme UI (Discord/Slack style)
- Live text streaming with content_block_delta handling
- Markdown rendering with react-markdown + remark-gfm
- Syntax highlighting with react-syntax-highlighter (One Dark)
- Collapsible high-tech tool cards with:
  - Tool-specific icons and colors
  - Compact summaries (Read, Glob, Bash, Edit, etc.)
  - Expandable JSON details
- Session history loading on resume
- Project directory selection
- Resume session toggle

Docker:
- Multi-container setup (backend + nginx frontend)
- Isolated Claude config directory
- Host network mode for backend

Built collaboratively by Neko (VPS Claude) and Web-UI Claude,
with Web-UI Claude implementing most frontend features while
running inside the interface itself (meta-programming!).

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

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

backend/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "claude-web-ui-backend",
+  "version": "1.0.0",
+  "description": "WebSocket backend for Claude Code JSON streaming",
+  "main": "server.js",
+  "type": "module",
+  "scripts": {
+    "start": "node server.js",
+    "dev": "node --watch server.js"
+  },
+  "dependencies": {
+    "express": "^4.18.2",
+    "ws": "^8.14.2",
+    "cors": "^2.8.5",
+    "uuid": "^9.0.0"
+  }
+}