feat(geoportal): building body labels (C1, C2, C3...) on map at zoom 17+

Extracts body suffix from cadastral_ref (e.g. "77102-C1" → "C1") and
displays as centered label on each building polygon. Only visible at
zoom 17+ to avoid clutter at lower zooms.

Applied to both geoportal map-viewer and parcel-sync map tab.
Uses siruta filter in parcel-sync tab.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/modules/geoportal/components/map-viewer.tsx

@@ -58,6 +58,7 @@ const LAYER_IDS = {
   terenuriLabel: "l-terenuri-label",
   cladiriFill: "l-cladiri-fill",
   cladiriLine: "l-cladiri-line",
+  cladiriLabel: "l-cladiri-label",
   selectionFill: "l-selection-fill",
   selectionLine: "l-selection-line",
   drawPolygonFill: "l-draw-polygon-fill",
@@ -438,6 +439,31 @@ export const MapViewer = forwardRef<MapViewerHandle, MapViewerProps>(
           paint: { "fill-color": "#3b82f6", "fill-opacity": 0.5 } });
         map.addLayer({ id: LAYER_IDS.cladiriLine, type: "line", source: SOURCES.cladiri, "source-layer": SOURCES.cladiri, minzoom: 14,
           paint: { "line-color": "#1e3a5f", "line-width": 0.6 } });
+        // Building body labels (C1, C2...) — only at high zoom to avoid clutter
+        map.addLayer({ id: LAYER_IDS.cladiriLabel, type: "symbol", source: SOURCES.cladiri, "source-layer": SOURCES.cladiri, minzoom: 17,
+          layout: {
+            "text-field": [
+              "case",
+              // Extract body suffix: "77102-C1" → "C1", "77102-C2" → "C2"
+              ["has", "cadastral_ref"],
+              ["case",
+                ["!=", ["index-of", "-C", ["get", "cadastral_ref"]], -1],
+                ["slice", ["get", "cadastral_ref"], ["+", ["index-of", "-C", ["get", "cadastral_ref"]], 1]],
+                "" // no "-C" suffix → no label
+              ],
+              ""
+            ],
+            "text-font": ["Noto Sans Regular"],
+            "text-size": 10,
+            "text-anchor": "center",
+            "text-allow-overlap": false,
+          },
+          paint: {
+            "text-color": "#1e40af",
+            "text-halo-color": "#ffffff",
+            "text-halo-width": 1.2,
+          },
+        });
 
         // === Selection highlight ===
         map.addLayer({ id: LAYER_IDS.selectionFill, type: "fill", source: SOURCES.terenuri, "source-layer": SOURCES.terenuri, minzoom: 13,

src/modules/parcel-sync/components/tabs/map-tab.tsx

@@ -46,6 +46,7 @@ const BASE_LAYERS = [
   "l-terenuri-label",
   "l-cladiri-fill",
   "l-cladiri-line",
+  "l-cladiri-label",
 ];
 
 /* ------------------------------------------------------------------ */