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/arcgis/client_test.go

@@ -66,3 +66,29 @@ func TestQueryRetriesThenFails(t *testing.T) {
 		t.Errorf("calls = %d, want 3 (1 + 2 retries)", calls)
 	}
 }
+
+// TestQueryStripsDistrictSuffix is a regression test: the portal appends the
+// district in parentheses, which used to hide the house number from the parser.
+func TestQueryStripsDistrictSuffix(t *testing.T) {
+	const env = `{"features":[{"value":"Медкадры улица, 1 (Заельцовский район)","attributes":{"address":"Медкадры улица, 1 (Заельцовский район)"}}]}`
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(env))
+	}))
+	defer ts.Close()
+
+	c := New(ts.URL, time.Second, 0)
+	rows, err := c.Query(context.Background(), "Медкадры улица 1")
+	if err != nil {
+		t.Fatalf("Query: %v", err)
+	}
+	if len(rows) != 1 {
+		t.Fatalf("rows = %d, want 1", len(rows))
+	}
+	if rows[0].Address != "Медкадры улица, 1" {
+		t.Errorf("district suffix not stripped: %q", rows[0].Address)
+	}
+	if rows[0].Unit.House != "1" {
+		t.Errorf("house not parsed at the boundary: %+v", rows[0].Unit)
+	}
+}