Extends the #355 perf-metrics registry (all behind the METRICS_PORT hard
gate — nullable instruments, no-op helpers when unset). New families:
- collab_doc_load_duration_seconds{size_bucket} — onLoadDocument timed on
the real DB-load paths only (the already-loaded early-return is skipped).
- size_bucket added to collab_store_duration_seconds; storeDocument returns
the ydoc byte length (reusing its single Y.encodeStateAsUpdate, no second
encode) so onStoreDocument observes size without extra cost.
- collab_docs_open (gauge, read-on-scrape via collect() from
hocuspocus.getDocumentsCount() — never inc/dec'd, so it can't drift) +
collab_doc_loads_total / collab_doc_unloads_total (afterLoad/afterUnload).
- collab_connect_duration_seconds — onConnect->connected, correlated by a
WeakMap keyed on the shared request (leak-free; the current client uses
one socket per document).
- collab_auth_duration_seconds — wraps onAuthenticate (success and failure).
- sizeBucket() shared helper (lt64k|lt256k|lt1m|ge1m, 4 bounded values).
The mcp_tool_duration_seconds histogram + collab_connect_timeouts_total
counter helpers are registered here but wired in pass 2 (MCP callback).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
agent_coder
96db9b6c7f