Add session activity indicators

[Umaaz]

Summary

• Adds a Claude Code plugin (claude-code-plugin/) with UserPromptSubmit and Stop hooks that write session state to /tmp/konductor-state/
• New activityWatcher.ts in the main process watches the state directory via chokidar and pushes updates to the renderer via IPC
• Status dots in the sidebar, session tiles, and focus view now show three activity states:
  • Green pulsing — Claude is working
  • Amber solid — waiting for user input
  • Green solid — ready (initial state)
• Includes .claude-plugin/marketplace.json registry so the plugin can be installed from the git repo in production

Test plan

• Start a session and verify the dot is solid green initially
• Send a message and verify the dot blinks green while Claude works
• After Claude responds, verify the dot turns amber (waiting for input)
• Kill a session and verify the dot turns red

🤖 Generated with Claude Code