[everpcpc]

Summary

Switch the admin UI's metric fetching from the Spring-style /actuator/metrics/* endpoints to the kmrs-native stats endpoints added in kmrs (GET /api/v1/stats/libraries, GET /api/v1/stats/server).

Changes

• statsApi gains libraries() and server(); actuatorApi loses metric/metricNames. The remaining actuator endpoints (health, sessions, scheduledtasks, logfile, shutdown) are untouched.
• StatsGrid reads uptime/CPU/memory from the server snapshot's process field; CPU is always a percent now, so the ratio-vs-percent branch goes away.
• ContentCounts takes libraries/collections/readlists from the server totals and series/books/file size from the libraries total.
• TaskExecutionPanel iterates the per-type rows (queue depth and execution metrics are merged server-side); failures are summed across types. The aggregate-only "all tasks" row is unreachable with the merged shape, so it and its taskExecution.allTasks locale keys are removed.
• LibraryCard finds its row in the shared libraries stats query; empty libraries report zeros, so the 404-means-zero workaround is gone.
• The panels share two query keys (admin/stats/server, admin/stats/libraries), replacing the per-metric/per-library request fan-out with two deduplicated queries.
• Deleted: useMetric.ts, admin/metric.ts.

Testing

• pnpm build (tsc + vite) and pnpm lint pass.