refactor!: make addrkit a multi-city address normalizer

- remove the events/outages module, ArcGIS adapter, portal config and event statuses
- add a configurable city dictionary/parser and make City part of StreetKey
- seed: read city/city_name, namespace IDs by city, keep structures distinct
- fix reliability: schema v2 with fail-closed load, deterministic ordering,
  input limits, config validation, atomic DB publish, LLM response caps
- add read-only shadow mode comparing the old ES path with addrkit
- breaking: registry.db must be re-seeded; config has no portal section

config.example.json

@@ -2,16 +2,18 @@
   "addr": ":6171",
   "data_path": "registry.db",
   "log_level": "info",
+  "cities": [
+    {
+      "name": "Новосибирск",
+      "aliases": ["нск", "новосиб", "новосибирская область", "нсо"]
+    }
+  ],
+  "default_city": "Новосибирск",
   "resolve": {
     "fuzzy_threshold": 0.82,
     "ambiguity_margin": 0.06,
     "max_candidates": 5
   },
-  "portal": {
-    "url": "${ADDRKIT_PORTAL_URL}",
-    "timeout_seconds": 2,
-    "retries": 1
-  },
   "llm": {
     "enabled": false,
     "url": "${ADDRKIT_LLM_URL}",