- Add a reusable ProjectNodeSelector component and hook RoutingTab to it for per-task node overrides
- Move default node and unavailable-node policy controls into the dedicated Node Routing settings section
- Add descriptive routing guidance text and project-level note in SettingsModal
- Expand dashboard tests for routing tab behavior and node routing settings UX
- Add node API typings and client methods plus a polling useNodes hook with visibility-triggered refresh
- Introduce NodesView with NodeCard, AddNodeModal, and NodeDetailModal to register, inspect, update, health-check, and remove nodes
- Wire the Nodes surface into the app shell/header and add project node assignment UI with project card node badges
- Add unit coverage for useNodes, NodesView, NodeCard, Header, and ProjectCard behavior, plus node-specific dashboard styling
