feat(admin-overlay): add gha.admin_overlay function + bump submodules

- New PostGIS function gha.admin_overlay(z,x,y,scope) returns admin0
  always, admin1 at z>=6, admin2 at z>=8 as separate MVT layers
- Bump eafw_geomanager_web (partners/CTA/major flag work)
- Bump eafw_geomapviewer (progressive admin overlay)

Author: HillaryKoros

db-init/10-admin-overlay-function.sql

@@ -0,0 +1,88 @@
+-- Overlay admin boundaries function:
+-- Always returns admin0; adds admin1 when z>=6; adds admin2 when z>=8.
+-- Each level is emitted as a distinct MVT layer so the frontend can style
+-- them independently with different line widths/colors and minzoom filters.
+--
+-- Frontend uses source-layer names: "admin0", "admin1", "admin2".
+-- Scope-aware: when scope='whca', uses gha.whca_admin0/1/2 tables.
+
+CREATE OR REPLACE FUNCTION gha.admin_overlay(
+    z integer, x integer, y integer,
+    scope text DEFAULT 'all'
+) RETURNS bytea
+LANGUAGE plpgsql STABLE
+AS $$
+DECLARE
+    out_mvt bytea := '';
+    tile_env geometry := ST_TileEnvelope(z, x, y);
+    tile_bbox geometry := ST_Transform(tile_env, 4326);
+    use_whca boolean := (COALESCE(scope, 'all') = 'whca');
+    level_mvt bytea;
+BEGIN
+    -- admin0: always included
+    IF use_whca THEN
+        SELECT ST_AsMVT(t, 'admin0', 4096, 'mvt_geom') INTO level_mvt
+        FROM (
+            SELECT country,
+                   ST_AsMVTGeom(ST_Transform(geom, 3857), tile_env, 4096, 256, false) AS mvt_geom
+            FROM gha.whca_admin0
+            WHERE geom && tile_bbox
+        ) t WHERE t.mvt_geom IS NOT NULL;
+    ELSE
+        SELECT ST_AsMVT(t, 'admin0', 4096, 'mvt_geom') INTO level_mvt
+        FROM (
+            SELECT country,
+                   ST_AsMVTGeom(ST_Transform(geom, 3857), tile_env, 4096, 256, false) AS mvt_geom
+            FROM gha.admin0
+            WHERE geom && tile_bbox
+        ) t WHERE t.mvt_geom IS NOT NULL;
+    END IF;
+    out_mvt := out_mvt || COALESCE(level_mvt, '');
+
+    -- admin1: z >= 6
+    IF z >= 6 THEN
+        IF use_whca THEN
+            SELECT ST_AsMVT(t, 'admin1', 4096, 'mvt_geom') INTO level_mvt
+            FROM (
+                SELECT country, name_1 AS region,
+                       ST_AsMVTGeom(ST_Transform(geom, 3857), tile_env, 4096, 256, false) AS mvt_geom
+                FROM gha.whca_admin1
+                WHERE geom && tile_bbox
+            ) t WHERE t.mvt_geom IS NOT NULL;
+        ELSE
+            SELECT ST_AsMVT(t, 'admin1', 4096, 'mvt_geom') INTO level_mvt
+            FROM (
+                SELECT country, name_1 AS region,
+                       ST_AsMVTGeom(ST_Transform(geom, 3857), tile_env, 4096, 256, false) AS mvt_geom
+                FROM gha.admin1
+                WHERE geom && tile_bbox
+            ) t WHERE t.mvt_geom IS NOT NULL;
+        END IF;
+        out_mvt := out_mvt || COALESCE(level_mvt, '');
+    END IF;
+
+    -- admin2: z >= 8
+    IF z >= 8 THEN
+        IF use_whca THEN
+            SELECT ST_AsMVT(t, 'admin2', 4096, 'mvt_geom') INTO level_mvt
+            FROM (
+                SELECT country, name_1 AS region, name_2 AS district,
+                       ST_AsMVTGeom(ST_Transform(geom, 3857), tile_env, 4096, 256, false) AS mvt_geom
+                FROM gha.whca_admin2
+                WHERE geom && tile_bbox
+            ) t WHERE t.mvt_geom IS NOT NULL;
+        ELSE
+            SELECT ST_AsMVT(t, 'admin2', 4096, 'mvt_geom') INTO level_mvt
+            FROM (
+                SELECT country, name_1 AS region, name_2 AS district,
+                       ST_AsMVTGeom(ST_Transform(geom, 3857), tile_env, 4096, 256, false) AS mvt_geom
+                FROM gha.admin2
+                WHERE geom && tile_bbox
+            ) t WHERE t.mvt_geom IS NOT NULL;
+        END IF;
+        out_mvt := out_mvt || COALESCE(level_mvt, '');
+    END IF;
+
+    RETURN out_mvt;
+END;
+$$;