Add guarded migration for existing v5 application, cluster, and resource connection tables missing uuid columns. Add Vitest, jsdom, and React Testing Library coverage for optimistic updates, canvas hooks, ingress, resource merging, viewport behavior, and v5 browser canvas and cluster flows.
Add the V5 server endpoint and UI action to restart coold over SSH with a fresh host token, plus Flux reconnect handling and coverage for the new backend, browser, and canvas test suites.
