docs: close doc-gaps (hub v0.11.0, onlyoffice:nextcloud occ internals, metricsDBPath verified)

- 05-hub-architecture.md: stale 'felhom-hub v0.6.3' -> v0.11.0 (design-draft note).
- auth-hub-sync-integrations.md: full onlyoffice:nextcloud occ command sequence.
- storage-monitoring-metrics.md: metricsDBPath verified to coincide with the volume-backed
  data_dir on the bootstrap guest (persists; hardcoding is latent fragility only).
- REORG-NOTES: gaps 2/3 CLOSED, gap 5 partially closed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

documentation/controller/storage-monitoring-metrics.md

@@ -178,8 +178,13 @@ the storage-management page via the agent host-metrics view).
 
 ### SQLite store (`store.go`)
 
-`NewMetricsStore(dbPath)` opens `modernc.org/sqlite` at
-`/opt/docker/felhom-controller/data/metrics.db` and **verifies WAL mode took effect** — it
+`NewMetricsStore(dbPath)` opens `modernc.org/sqlite` at `metricsDBPath`, hardcoded in `main.go:189` to
+`/opt/docker/felhom-controller/data/metrics.db`. On the live bootstrap-managed guest this **coincides
+with the volume-backed `data_dir`** (the `felhom-controller-data` volume mounts at
+`/opt/docker/felhom-controller`; `data_dir: /opt/docker/felhom-controller/data`), so metrics persist
+across restarts. The path is hardcoded rather than derived from `cfg.Paths.DataDir` — a latent fragility
+(would diverge if `data_dir` were reconfigured), tracked as a low-priority backlog item, not a live bug.
+The store **verifies WAL mode took effect** — it
 errors out if `PRAGMA journal_mode=WAL` does not return `"wal"` (`store.go:27-34`), then sets
 `synchronous=NORMAL` and `busy_timeout=5000`. Two tables: `system_metrics` and
 `container_metrics`, with ts indices (`:48-77`). Queries downsample into time buckets