[AZ-370] Refactor C17: status / point-type enums + AC RT2 update

Replaces bare strings with two enums in Common/Enums/:
  RegionStatus { Queued, Processing, Completed, Failed }
  RoutePointType { Start, End, Action, Intermediate }

Adds a Dapper EnumStringTypeHandler<T> (DataAccess/TypeHandlers/)
that round-trips enums to/from lowercase strings, registered once
at startup via DapperEnumTypeHandlers.RegisterAll(). DataAccess now
references Common (project ref) so entities can carry the enum types.

Sites converted: RegionService (5), RouteProcessingService (3),
RoutePointGraphBuilder (4), entity Status/PointType columns. Log
message and summary file format preserved via .ToLowerInvariant().

API JSON contract preserved by adding JsonStringEnumConverter with
JsonNamingPolicy.CamelCase to the http JSON options — single-word
enum members serialize to the same lowercase strings as before.

DTO renamed: Common.DTO.RegionStatus -> RegionStatusResponse to
free the RegionStatus name for the new enum (forced by the task's
explicit enum name); the renamed DTO has no public-API impact at
the JSON wire level. Stale doc references updated.

AC RT2 in _docs/00_problem/acceptance_criteria.md now lists all 4
point types (start/end/action/intermediate).

Tests: 171 / 171 unit + 5 / 5 smoke green (was 141 + 5; +30 new tests
covering type handler round-trip, set/parse, unknown-value rejection,
idempotent registration, and the AC RT2 doc check).

Co-authored-by: Cursor <cursoragent@cursor.com>

_docs/00_problem/acceptance_criteria.md

@@ -25,7 +25,7 @@
 | # | Criterion | Measurable Value | Source |
 |---|----------|-----------------|--------|
 | RT1 | Points interpolated at correct interval | Intermediate points every ~200m along path | RouteService (InterpolatePoints) |
-| RT2 | Point types correctly assigned | "original" for input waypoints, "intermediate" for generated | RoutePointEntity.PointType |
+| RT2 | Point types correctly assigned | "start" for first waypoint, "end" for last waypoint, "action" for middle waypoints, "intermediate" for generated points | RoutePointEntity.PointType |
 | RT3 | Total distance calculated | Haversine sum matches within acceptable precision | RouteService.CreateRoute |
 | RT4 | Geofence filtering applied | Only points inside geofence rectangles generate regions | RouteService (point-in-rectangle check) |
 | RT5 | ZIP archive within size limit | ≤ 50 MB | RouteProcessingService ZIP generation |

_docs/02_document/00_discovery.md

@@ -34,7 +34,7 @@ satellite-provider/
 │   │   ├── GeoPoint.cs
 │   │   ├── GeofencePolygon.cs
 │   │   ├── RegionRequest.cs
-│   │   ├── RegionStatus.cs
+│   │   ├── RegionStatusResponse.cs
 │   │   ├── RoutePoint.cs
 │   │   ├── RoutePointDto.cs
 │   │   ├── RouteResponse.cs

_docs/02_document/04_verification_log.md

@@ -27,7 +27,7 @@ All classes, interfaces, and types mentioned in documentation were cross-referen
 - **Service implementations** (7/7): TileService, RegionService, RouteService, GoogleMapsDownloaderV2, RegionProcessingService, RouteProcessingService, RegionRequestQueue ✓
 - **Repositories** (6/6): ITileRepository, IRegionRepository, IRouteRepository, TileRepository, RegionRepository, RouteRepository ✓
 - **Config classes** (4/4): MapConfig, StorageConfig, ProcessingConfig, DatabaseConfig ✓
-- **DTOs** (10/10): GeoPoint, Direction, TileMetadata, RegionRequest, RegionStatus, RouteResponse, RoutePoint, RoutePointDto, CreateRouteRequest, GeofencePolygon ✓
+- **DTOs** (10/10): GeoPoint, Direction, TileMetadata, RegionRequest, RegionStatusResponse, RouteResponse, RoutePoint, RoutePointDto, CreateRouteRequest, GeofencePolygon ✓
 - **Utilities** (1/1): GeoUtils ✓
 - **Infrastructure** (1/1): DatabaseMigrator ✓
 

_docs/02_document/components/01_common/description.md

@@ -24,8 +24,8 @@ This component defines the service contracts that other components implement:
 ### Interface: IRegionService
 | Method | Input | Output | Async | Error Types |
 |--------|-------|--------|-------|-------------|
-| `RequestRegionAsync` | id, lat, lon, sizeMeters, zoomLevel, stitchTiles | `RegionStatus` | Yes | Exception |
-| `GetRegionStatusAsync` | Guid id | `RegionStatus?` | Yes | Exception |
+| `RequestRegionAsync` | id, lat, lon, sizeMeters, zoomLevel, stitchTiles | `RegionStatusResponse` | Yes | Exception |
+| `GetRegionStatusAsync` | Guid id | `RegionStatusResponse?` | Yes | Exception |
 | `ProcessRegionAsync` | Guid id, CancellationToken | void | Yes | RateLimitException, HttpRequestException, TimeoutException |
 
 ### Interface: IRouteService

_docs/02_document/modules/common_interfaces.md

@@ -13,8 +13,8 @@ Service contracts defining the application's core operations. Implementations li
 - `DownloadAndStoreSingleTileAsync(double latitude, double longitude, int zoomLevel, CancellationToken) → Task<TileMetadata>`: download one tile by lat/lon and persist (added in AZ-311)
 
 ### IRegionService
-- `RequestRegionAsync(Guid id, double lat, double lon, double sizeMeters, int zoomLevel, bool stitchTiles) → Task<RegionStatus>`: creates a region record and enqueues for async processing
-- `GetRegionStatusAsync(Guid id) → Task<RegionStatus?>`: retrieves current status of a region request
+- `RequestRegionAsync(Guid id, double lat, double lon, double sizeMeters, int zoomLevel, bool stitchTiles) → Task<RegionStatusResponse>`: creates a region record and enqueues for async processing
+- `GetRegionStatusAsync(Guid id) → Task<RegionStatusResponse?>`: retrieves current status of a region request
 - `ProcessRegionAsync(Guid id, CancellationToken) → Task`: executes tile downloading, CSV/summary generation, optional stitching
 
 ### IRouteService

_docs/02_document/modules/services_region.md

@@ -6,8 +6,8 @@ End-to-end region processing pipeline: API request handling → queue → backgr
 ## Public Interface
 
 ### RegionService (implements IRegionService)
-- `RequestRegionAsync(...)`: creates `RegionEntity` with status "queued", enqueues a `RegionRequest`, returns `RegionStatus`
-- `GetRegionStatusAsync(Guid id)`: reads region record and maps to `RegionStatus`
+- `RequestRegionAsync(...)`: creates `RegionEntity` with status `RegionStatus.Queued`, enqueues a `RegionRequest`, returns `RegionStatusResponse`
+- `GetRegionStatusAsync(Guid id)`: reads region record and maps to `RegionStatusResponse`
 - `ProcessRegionAsync(Guid id, CancellationToken)`: the main processing pipeline — see Internal Logic
 
 ### RegionProcessingService (BackgroundService)
@@ -71,7 +71,7 @@ Each sets status to "failed" and writes an error summary file.
 
 ## Data Models
 - Input: `RegionRequest` (queue message)
-- Output: `RegionStatus` (API response), CSV files, summary files, stitched images
+- Output: `RegionStatusResponse` (API response), CSV files, summary files, stitched images
 - Persistence: `RegionEntity`
 
 ## Configuration

_docs/_autodev_state.md

@@ -8,7 +8,7 @@ status: in_progress
 sub_step:
   phase: 4
   name: execution
-  detail: "K=3 review (16-18) PASS; next batch 19 candidate AZ-370"
+  detail: "batch 19 (AZ-370) complete; K=3 review fires after batch 21"
 retry_count: 0
 cycle: 1
 tracker: jira