Review feedback on this PR (mara): "i think the component should be
shared. motion setting is missing." Both addressed:
- `settings-storage.ts` (generic localStorage hook), `theme-apply.ts`,
`motion-apply.ts`, and `SettingsMenu.tsx`/`.css` all move from
swarm-ui's `lib/`/`shell/` into `@hive/shared/src/settings/` —
agent's previous local copies are deleted outright rather than kept
as a second implementation. One component, `Badge` trigger
everywhere (already used elsewhere in swarm-ui, so not a new visual
language there either) — storage keys stay caller-owned (`themeKey`/
`motionKey` props + matching `useApplyThemeOverride`/
`useApplyMotionOverride` calls at each package's single mount point)
so agent and swarm-ui keep fully independent, non-colliding
persisted settings.
- Agent's settings menu now includes the motion row, matching
swarm-ui's. No animation in the agent package is gated behind
`data-motion` yet — same as when swarm-ui first built this plumbing
ahead of having a consumer — so it's currently inert there, ready for
whenever agent grows a motion-guarded animation.
- swarm-ui's own theme default flips to `'dark'` as part of this move
(`theme-apply.ts`'s new default), superseding PR #3715 — that PR
becomes redundant once this lands and will be closed rather than
merged, to avoid the two colliding on the same file.
Verified end-to-end with real screenshots on both pages: shared
component renders identically (Badge trigger, theme+motion rows, dark
default) on agent's mock server and a static rebuild of swarm-ui's
dist.