* feat: add a Concurrency page to the dashboard

Lists every concurrency strategy in the tenant (task, workflow and shared
scopes) with live key, running and queued counts, and shows a strategy's
keys in the side panel.

- API: GET /api/v1/stable/tenants/{tenant}/concurrency/strategies and
  .../strategies/{scope}/{strategy}/keys, with search, onlyQueued and
  offset pagination.
- Repository: ConcurrencyOverviewRepository; strategy summaries are
  cached for 5s per tenant.
- Frontend: strategies table with scope filter, pagination and refresh
  control; totals strip; keys side panel; filters kept in the URL.
- Moves useLiveClock to src/hooks and makes its tick interval
  configurable; moves StatCell to components/v1/molecules.

* chore: regenerate SDK REST clients for the concurrency endpoints

* fix: declare x-payloads on the concurrency operations

* fix: address review feedback on the concurrency overview

- List strategies on the latest workflow version even when the stale
  deactivation has cleared is_active on idle ones; shared strategies come
  from the steps that reference them instead of the active-only list.
- Count matching keys separately, so a page past the last key still
  reports the total.
- Stop the strategy summary cache in the repository cleanup.
- Describe GROUP_ROUND_ROBIN as a per-key cap with a per-key queue.
- Add godoc to the exported concurrency declarations.

* fix: use the suggested empty state and round-robin copy

* review

* remove llm useless comments

* fix test

* remove limit strategy tooltips

* remove concurrency page description

* remove keys footer info tooltip

* remove filters and use neutral limit strategy colors

* show strategy details in the keys drawer

* regenerate typescript fetch client

* fix keys refresh query key

* hide the concurrency page behind a feature flag

* use the tenant pool handle for concurrency queries