feat(gamification): show API key names on the leaderboard (#12385)

The Leaderboard rendered apiKeyId.slice(0, 8)… under a column translated as "name". The route now enriches each entry with the key's display name — route-local, so the shared getTopN helper and the federation leaderboard stay id-only — and the page renders name ?? shortId with the full id in a title attribute. The lookup selects only id and name from api_keys, chunked at 200 ids, with unknown ids and blank names omitted; no key material leaves the DB layer.

Validated in a combined worktree with all 25 PRs of this batch boarded together: typecheck:core clean, 443/443 node-runner tests plus 14/14 vitest across every test file the batch touches, and check-changelog-integrity, check:cycles (418 files), check:provider-consistency (272 REGISTRY entries, 355 canonical providers), check:docs-counts, check:docs-sync (42 locales) and check-file-size all green.

Thanks @pacocartones.