Add V1 selected area map overlay

docs/API_CONTRACTS.md

@@ -122,7 +122,24 @@ Soft-delete in V1 preferred. Hard-delete only if storage cleanup is also impleme
 
 ### GET `/api/v1/projects/{project_id}/areas`
 
-Returns areas for a project.
+Returns areas for a project. Area responses include persisted AOI geometry as
+GeoJSON so the frontend can display the selected area in the map workbench.
+
+```json
+{
+  "id": "uuid",
+  "project_id": "uuid",
+  "name": "Geel Centrum AOI",
+  "original_crs": "EPSG:4326",
+  "area_m2": 1234.5,
+  "created_at": "timestamp",
+  "geometry_type": null,
+  "geometry": {
+    "type": "MultiPolygon",
+    "coordinates": []
+  }
+}
+```
 
 ### POST `/api/v1/projects/{project_id}/areas`
 

docs/CODEX_EXECUTION_LOG.md

@@ -1,3 +1,19 @@
+## Sprint 20 V1 selected area map overlay (2026-06-17)
+
+Changed:
+- Added GeoJSON geometry serialization for project areas so persisted AOIs can be displayed by the map workbench.
+- Added a dedicated MapLibre area overlay layer with separate visibility and opacity controls.
+- Added area list actions and map workspace controls to select the active AOI.
+- Updated API/frontend docs, changelog and TODO status for selected area display.
+
+Tested:
+- Pending validation in this pass: backend compile, backend pytest, readiness, frontend typecheck/build, Alembic checks and deploy/browser smoke.
+
+Known limitations:
+- Area geometry is displayed as a simple filled/outlined GeoJSON overlay; no drawing/editing workflow is introduced in this pass.
+
+Next recommended pass:
+- Add a small V1 workflow polish pass for richer dataset/area empty states and a fixture-driven end-to-end browser smoke once the new build is deployed.
 ## Sprint 19 V1 map workbench controls (2026-06-17)
 
 Changed:

docs/TODO.md

@@ -16,6 +16,7 @@ This file now starts with the current implementation status. Older preparation/b
 - [x] Backend FastAPI foundation, health endpoint and service structure.
 - [x] React/TypeScript frontend foundation and MapLibre workbench.
 - [x] Map layer visibility, opacity and feature property inspection.
+- [x] Selected project area/AOI map overlay with visibility and opacity controls.
 - [x] SQLAlchemy/PostGIS ORM models and Alembic migration chain through Sprint 9.
 - [x] Dataset upload, storage metadata and vector feature persistence.
 - [x] Raster metadata and raster operation service boundaries.
@@ -89,6 +90,7 @@ This file now starts with the current implementation status. Older preparation/b
 - [x] Map Workbench basis
 - [x] Map layer controls
 - [x] Feature property inspector
+- [x] Selected area display
 
 ## 4. Project & Area API