Outage providers: licence-gated registry, ODIN adapter, /outages API, admin tab (Refs #184)

Part 1 of 2 for server-26#184 (map layer + incident cross-match follow in batch 3).

- app/internal/outages/: same gate as the camera registry -- settings doc
  config/outage_providers, every provider OFF by default, unreadable settings
  fail closed, stubs never enable, gated licences need acknowledge_licence
  stored with who/when plus an audit_log write as a precondition, and the
  acknowledgement is bound to the licence status it was given for.
  Reuses cameras.base Licence/LicenceInfo/get_json/safe_error/require_parsed.
- ODIN adapter (Licence.UNVERIFIED, gated): public county-level API verified
  first-hand against https://odin.ornl.gov/v3/api-docs -- /odi?format=JSON
  (counts, start, ETR), /odi/map?scale=COUNTY (county name, bbox, label
  point), /odi/status (utility freshness). Schema canary on all three.
  metersServed is utility-wide, so customers_served stays None.
- Stubs: poweroutage_us (paid), coned_oru / nyseg_rge / central_hudson
  storm centers and eagle_i_live (agreement required).
- GET /outages (signed-in) returns areas + per-provider credit/health and a
  status (ok / none_enabled / no_source / error) so an empty layer is never
  ambiguous. /admin/outage-providers GET + PUT, admin only, 409 with
  requires_acknowledgement like cameras.
- Frontend: c2api getOutages/listOutageProviders/setOutageProvider, types,
  Admin -> Outage providers tab (deep link /admin#outages).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

drb-c2-core/app/main.py

@@ -19,6 +19,7 @@ from app.internal.auth import (
 )
 from app.routers import nodes, systems, calls, upload, tokens, incidents, alerts, admin, trips, places, links, users
 from app.routers import enrollment, media, org, waitlist, telemetry, replay, traffic, cameras
+from app.routers import outages
 from app.routers import discord as discord_router
 from app.routers import discord_link as discord_link_router
 from app.internal import dynsec
@@ -146,6 +147,8 @@ app.include_router(places.router,    dependencies=[Depends(require_service_or_fi
 app.include_router(traffic.router,   dependencies=[Depends(require_service_or_firebase_token)])
 app.include_router(cameras.router,   dependencies=[Depends(require_service_or_firebase_token)])
 app.include_router(cameras.admin_router)  # auth: admin only, per endpoint (needs the principal for audit)
+app.include_router(outages.router,   dependencies=[Depends(require_service_or_firebase_token)])
+app.include_router(outages.admin_router)  # auth: admin only, per endpoint (needs the principal for audit)
 app.include_router(upload.router)    # auth is per-node, handled inline
 app.include_router(admin.router)     # auth is per-endpoint (read: firebase, write: admin)
 app.include_router(replay.router)    # auth: admin only (every route spends or reads a replay run)