### Added
- New **Tools** dialog accessible from the 3-dots menu, listing all currently loaded tools with their runtime, description, and env status badges (Ready / Configured / env missing).
- Environment variable management panel within the Tools dialog: view which env vars each tool requires, see which tools depend on each variable, and set/clear values inline.
- Sensitive env vars (containing API_KEY, SECRET, TOKEN, etc.) are never sent to the client — only a "Configured" / "Not set" indicator is shown. Non-sensitive vars display their current value.