fix(outages): parse portal address at the boundary; strip district suffix

The outages portal appends the district in parentheses, e.g.
"Медкадры улица, 1 (Заельцовский район)". That suffix hid the house number
from the parser, so every portal address failed house matching and /v1/outages
always returned empty.

- address: NormalizeText drops a trailing "(...)" group (root fix, benefits
  every source)
- outages: introduce HouseUnit; the ArcGIS adapter parses the (cleaned) address
  at the boundary and stores the structured unit; MatchingHouse matches on the
  unit (with a parse fallback for sources that only provide text)
- config: portal.url is now optional (core runs without the events module)
- httpapi: always return "outages": [] (no more omitempty); report
  "detail" when the events module is not configured
- tests: regression coverage for the portal district format

internal/adapters/httpapi/server.go

@@ -79,9 +79,10 @@ type outagesResponse struct {
 	Status      address.Status   `json:"status"`
 	Address     string           `json:"address,omitempty"`
 	District    string           `json:"district,omitempty"`
-	Outages     []outages.Outage `json:"outages,omitempty"`
+	Outages     []outages.Outage `json:"outages"`
 	AsOf        string           `json:"as_of,omitempty"`
 	DataVersion string           `json:"data_version,omitempty"`
+	Detail      string           `json:"detail,omitempty"`
 }
 
 func (s *Server) handleOutages(w http.ResponseWriter, r *http.Request) {
@@ -97,6 +98,7 @@ func (s *Server) handleOutages(w http.ResponseWriter, r *http.Request) {
 		Address:     res.Address,
 		District:    res.District,
 		DataVersion: res.DataVersion,
+		Outages:     []outages.Outage{},
 	}
 	if res.Status != address.StatusFound {
 		// No canonical address => nothing to query. Return the resolver's
@@ -104,6 +106,13 @@ func (s *Server) handleOutages(w http.ResponseWriter, r *http.Request) {
 		writeJSON(w, http.StatusOK, out)
 		return
 	}
+	if s.outages == nil {
+		// The events module is optional and off when portal.url is empty.
+		out.Status = address.StatusInfra
+		out.Detail = "outages source is not configured"
+		writeJSON(w, http.StatusOK, out)
+		return
+	}
 
 	raw, err := s.outages.Query(ctx, res.Address)
 	if err != nil {