chore: regenerate stale .pi-map.md / .pi-map.index.md project maps

Project map had drifted: claimed recharts unused (was used), ObservabilityPage.tsx
exists (refactored to service-tabs/), missed JellyfinNowPlayingWidget +
authentik/backups service types. Regenerate to reflect post-change reality:
new Qbittorrent/LineSeriesChart/Prometheus{Gauge,Mean}Widget files,
service_data.py/qbittorrent_store.py, canonical prometheus-charting +
service-storage specs, archived changes.

backend/src/media_library_viewer_api/routers/.pi-map.index.md

@@ -2,7 +2,7 @@
 dir: backend/src/media_library_viewer_api/routers
 
 ## role
-FastAPI router package that exposes all REST API endpoints for the media library viewer backend, organized by domain (files, media, jobs, backups, dashboard, monitoring, services, settings, tasks, users, widgets).
+FastAPI router package that defines all HTTP API endpoints for the media library viewer backend, organizing routes by domain (auth, backups, dashboards, files, jobs, media, monitoring, services, settings, tasks, widgets).
 ## parent
 index: backend/src/media_library_viewer_api/.pi-map.index.md
 map: backend/src/media_library_viewer_api/.pi-map.md
@@ -10,8 +10,10 @@ map: backend/src/media_library_viewer_api/.pi-map.md
 -
 ## files
 - __init__.py
+- authentik_users.py
 - backups.py
 - dashboard.py
+- dashboards.py
 - files.py
 - jobs.py
 - media.py
@@ -19,14 +21,12 @@ map: backend/src/media_library_viewer_api/.pi-map.md
 - services.py
 - settings.py
 - tasks.py
-- users.py
-- users_impl.py
 - widgets.py
 ## links
 index: backend/src/media_library_viewer_api/routers/.pi-map.index.md
 map: backend/src/media_library_viewer_api/routers/.pi-map.md
 ## workflows
 - change routers behavior
-  read: __init__.py, backups.py, dashboard.py
+  read: __init__.py, authentik_users.py, backups.py
 ## dirty
 -