feat: add parcel-sync module (eTerra ANCPI integration with PostGIS)

- 31 eTerra layer catalog (terenuri, cladiri, documentatii, administrativ)
- Incremental sync engine (OBJECTID comparison, only downloads new features)
- PostGIS-ready Prisma schema (GisFeature, GisSyncRun, GisUat models)
- 7 API routes (/api/eterra/login, count, sync, features, layers/summary, progress, sync-status)
- Full UI with 3 tabs (Sincronizare, Parcele, Istoric)
- Env var auth (ETERRA_USERNAME / ETERRA_PASSWORD)
- Real-time sync progress tracking with polling

src/modules/parcel-sync/services/esri-geojson.ts

@@ -0,0 +1,82 @@
+/**
+ * ESRI → GeoJSON conversion for eTerra features.
+ */
+
+import type { EsriFeature } from "./eterra-client";
+
+export type GeoJsonPolygon = { type: "Polygon"; coordinates: number[][][] };
+export type GeoJsonMultiPolygon = {
+  type: "MultiPolygon";
+  coordinates: number[][][][];
+};
+
+export type GeoJsonFeature = {
+  type: "Feature";
+  properties: Record<string, unknown>;
+  geometry: GeoJsonPolygon | GeoJsonMultiPolygon;
+};
+
+export type GeoJsonFeatureCollection = {
+  type: "FeatureCollection";
+  features: GeoJsonFeature[];
+};
+
+const ringArea = (ring: number[][]) => {
+  let area = 0;
+  for (let i = 0; i < ring.length - 1; i++) {
+    const curr = ring[i]!;
+    const next = ring[i + 1]!;
+    area += curr[0]! * next[1]! - next[0]! * curr[1]!;
+  }
+  return area / 2;
+};
+
+const isClockwise = (ring: number[][]) => ringArea(ring) < 0;
+
+const closeRing = (ring: number[][]) => {
+  if (ring.length === 0) return ring;
+  const first = ring[0]!;
+  const last = ring[ring.length - 1]!;
+  return first[0] !== last[0] || first[1] !== last[1]
+    ? [...ring, [first[0]!, first[1]!]]
+    : ring;
+};
+
+const ringsToPolygons = (rings: number[][][]) => {
+  const polygons: number[][][][] = [];
+  let current: number[][][] | null = null;
+  for (const ring of rings) {
+    const closed = closeRing(ring);
+    if (closed.length < 4) continue;
+    if (isClockwise(closed) || !current) {
+      if (current) polygons.push(current);
+      current = [closed];
+    } else {
+      current.push(closed);
+    }
+  }
+  if (current) polygons.push(current);
+  return polygons;
+};
+
+export const esriToGeojson = (
+  features: EsriFeature[],
+): GeoJsonFeatureCollection => {
+  const geoFeatures: GeoJsonFeature[] = [];
+  for (const feature of features) {
+    const rings = feature.geometry?.rings;
+    if (!rings?.length) continue;
+    const polygons = ringsToPolygons(rings);
+    if (!polygons.length) continue;
+    const geometry: GeoJsonPolygon | GeoJsonMultiPolygon =
+      polygons.length === 1
+        ? { type: "Polygon", coordinates: polygons[0]! }
+        : { type: "MultiPolygon", coordinates: polygons };
+    geoFeatures.push({
+      type: "Feature",
+      properties: feature.attributes ?? {},
+      geometry,
+    });
+  }
+  return { type: "FeatureCollection", features: geoFeatures };
+};