refactor: enhance artifact system, security, and terminal command handling

- Add basic HTTP authentication (express-basic-auth)
- Improve artifact tool with better source type handling (command_output, file, text)
- Update agent prompt with clearer artifact usage patterns
- Refactor tmux command execution to use execFile for safer argument handling
- Add UI cancellation capability for in-progress operations
- Switch session dumps to use util.inspect for better formatting
- Update artifact tool schema to require title parameter first

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

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

packages/voice-assistant/package.json

@@ -23,6 +23,7 @@
     "ai": "^5.0.76",
     "dotenv": "^17.2.3",
     "express": "^4.18.2",
+    "express-basic-auth": "^1.2.1",
     "lucide-react": "^0.546.0",
     "openai": "^4.20.0",
     "playwright": "^1.56.1",