Desktop hooks

A hook earns its own file only when it is reused or owns a real React lifecycle, such as a subscription, effect, or ref. Otherwise, inline it at its call site. New multi-file hook internals belong in a domain directory instead of adding more files to this root.

Follow the repository-wide code placement guide.

Action factories should read Zustand actions from useAppStore.getState() at invocation time instead of accepting store setters as parameters. This keeps them usable from relay routing and directly testable without a renderer.

Components subscribe to the narrowest store value they render, ideally a per-room value such as state.codexRuntimeByRoom[roomId]. App-level code passes only effectful capabilities that cannot live in the store. Do not add selector bundles, view-model prop assemblers, callback-proxy layers, or compatibility re-export files; derived selectors belong beside their store slice.