[AZ-373] Refactor C20: drop MapsVersion from new writes (option a)

- Stop writing "downloaded_YYYY-MM-DD" into tiles.maps_version: new rows
  bind @MapsVersion to NULL via TileService.BuildTileEntity.
- Retain the tiles.maps_version column (coderule.mdc forbids unprompted
  column drops); pre-existing rows keep their values for forensics.
- Remove MapsVersion property from DownloadTileResponse (API wire shape)
  and TileMetadata (internal DTO); OpenAPI schema regenerates from the
  DTO via Swashbuckle.
- Add 3 AC tests in TileServiceTests covering the captured-entity write
  (AC-1) and the DTO/wire-shape removal (AC-2).
- Update integration-test local DTO + console output; refresh docs in
  common_dtos.md, services_tile_service.md, data_model.md.
- Archive AZ-373 task file: todo/ -> done/.

174 unit + 5 smoke pass.

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

SatelliteProvider.Api/Program.cs

@@ -179,7 +179,6 @@ async Task<IResult> GetTileByLatLon([FromQuery] double Latitude, [FromQuery] dou
         TileSizeMeters = tile.TileSizeMeters,
         TileSizePixels = tile.TileSizePixels,
         ImageType = tile.ImageType,
-        MapsVersion = tile.MapsVersion,
         Version = tile.Version,
         FilePath = tile.FilePath,
         CreatedAt = tile.CreatedAt,

SatelliteProvider.Common/DTO/DownloadTileResponse.cs

@@ -9,7 +9,6 @@ public record DownloadTileResponse
     public double TileSizeMeters { get; set; }
     public int TileSizePixels { get; set; }
     public string ImageType { get; set; } = string.Empty;
-    public string? MapsVersion { get; set; }
     public int? Version { get; set; }
     public string FilePath { get; set; } = string.Empty;
     public DateTime CreatedAt { get; set; }

SatelliteProvider.Common/DTO/TileMetadata.cs

@@ -11,7 +11,6 @@ public class TileMetadata
     public double TileSizeMeters { get; set; }
     public int TileSizePixels { get; set; }
     public string ImageType { get; set; } = string.Empty;
-    public string? MapsVersion { get; set; }
     public int? Version { get; set; }
     public string FilePath { get; set; } = string.Empty;
     public DateTime CreatedAt { get; set; }

SatelliteProvider.IntegrationTests/Models.cs

@@ -9,7 +9,6 @@ public record DownloadTileResponse
     public double TileSizeMeters { get; set; }
     public int TileSizePixels { get; set; }
     public string ImageType { get; set; } = string.Empty;
-    public string? MapsVersion { get; set; }
     public string FilePath { get; set; } = string.Empty;
     public DateTime CreatedAt { get; set; }
     public DateTime UpdatedAt { get; set; }

SatelliteProvider.IntegrationTests/TileTests.cs

@@ -45,7 +45,6 @@ public static class TileTests
         Console.WriteLine($"  Tile Size (meters): {tile.TileSizeMeters:F2}");
         Console.WriteLine($"  Tile Size (pixels): {tile.TileSizePixels}");
         Console.WriteLine($"  Image Type: {tile.ImageType}");
-        Console.WriteLine($"  Maps Version: {tile.MapsVersion}");
         Console.WriteLine($"  File Path: {tile.FilePath}");
         Console.WriteLine($"  Created At: {tile.CreatedAt:yyyy-MM-dd HH:mm:ss}");
 

SatelliteProvider.Services.TileDownloader/TileService.cs

@@ -154,7 +154,7 @@ public class TileService : ITileService
             TileSizeMeters = downloaded.TileSizeMeters,
             TileSizePixels = _mapConfig.TileSizePixels,
             ImageType = "jpg",
-            MapsVersion = $"downloaded_{now:yyyy-MM-dd}",
+            MapsVersion = null,
             Version = null,
             FilePath = downloaded.FilePath,
             CreatedAt = now,
@@ -175,7 +175,6 @@ public class TileService : ITileService
             TileSizeMeters = entity.TileSizeMeters,
             TileSizePixels = entity.TileSizePixels,
             ImageType = entity.ImageType,
-            MapsVersion = entity.MapsVersion,
             Version = entity.Version,
             FilePath = entity.FilePath,
             CreatedAt = entity.CreatedAt,

SatelliteProvider.Tests/TileServiceTests.cs

@@ -207,6 +207,54 @@ public class TileServiceTests
         captured!.Version.Should().BeNull("AZ-357: new code never writes the deprecated year-based version");
     }
 
+    [Fact]
+    public void BuildTileEntity_DoesNotPopulateMapsVersion_AZ373_AC1()
+    {
+        // Arrange
+        var downloader = new Mock<ISatelliteDownloader>();
+        var tileRepo = new Mock<ITileRepository>();
+        TileEntity? captured = null;
+        tileRepo
+            .Setup(r => r.InsertAsync(It.IsAny<TileEntity>()))
+            .Callback<TileEntity>(e => captured = e)
+            .ReturnsAsync(Guid.NewGuid());
+        downloader
+            .Setup(d => d.DownloadSingleTileAsync(It.IsAny<double>(), It.IsAny<double>(), It.IsAny<int>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new DownloadedTileInfoV2(1, 2, 18, 47.46, 37.65, "tiles/18/1/2.jpg", 100.0));
+
+        var service = BuildService(downloader, tileRepo);
+
+        // Act
+        _ = service.DownloadAndStoreSingleTileAsync(47.46, 37.65, 18).GetAwaiter().GetResult();
+
+        // Assert
+        captured.Should().NotBeNull();
+        captured!.MapsVersion.Should().BeNull(
+            "AZ-373 option (a): new code never writes a MapsVersion value; the column is retained for forensics on pre-existing rows only");
+    }
+
+    [Fact]
+    public void DownloadTileResponse_DoesNotExposeMapsVersion_AZ373_AC2()
+    {
+        // Act
+        var property = typeof(DownloadTileResponse).GetProperty("MapsVersion");
+
+        // Assert
+        property.Should().BeNull(
+            "AZ-373 AC-2 option (a): MapsVersion is removed from the HTTP response shape");
+    }
+
+    [Fact]
+    public void TileMetadata_DoesNotExposeMapsVersion_AZ373_AC1()
+    {
+        // Act
+        var property = typeof(TileMetadata).GetProperty("MapsVersion");
+
+        // Assert
+        property.Should().BeNull(
+            "AZ-373 AC-1: TileMetadata DTO no longer carries MapsVersion (consistent with the HTTP response removal)");
+    }
+
     [Fact]
     public async Task GetTileAsync_KnownId_ReturnsMappedMetadata()
     {

_docs/02_document/data_model.md

@@ -96,7 +96,7 @@ Stores metadata for downloaded satellite imagery tiles. Each tile is a single im
 | tile_size_meters | DOUBLE PRECISION | NOT NULL | Ground coverage in meters |
 | tile_size_pixels | INT | NOT NULL | Image dimension in pixels |
 | image_type | VARCHAR(10) | NOT NULL | Image format (e.g., "jpg") |
-| maps_version | VARCHAR(50) | | Google Maps version string |
+| maps_version | VARCHAR(50) | | Legacy free-form provider tag; post-AZ-373 new rows write NULL (column retained for forensics on pre-existing rows) |
 | version | INT | NOT NULL, DEFAULT 2025 | Year-based versioning for cache invalidation |
 | file_path | VARCHAR(500) | NOT NULL | Relative path to stored image |
 | tile_x | INT | NOT NULL | Tile X coordinate (Slippy Map) |

_docs/02_document/modules/common_dtos.md

@@ -30,7 +30,7 @@ Represents a single map tile with its spatial bounds.
 Metadata about a stored tile (mirrors `TileEntity` but without DB-specific concerns).
 - `Id` (Guid), `TileZoom`, `TileX`, `TileY` (int), `Latitude`, `Longitude` (double)
 - `TileSizeMeters` (double), `TileSizePixels` (int), `ImageType` (string)
-- `MapsVersion` (string?), `Version` (int), `FilePath` (string)
+- `Version` (int?), `FilePath` (string)
 - `CreatedAt`, `UpdatedAt` (DateTime)
 
 ### RegionRequest

_docs/02_document/modules/services_tile_service.md

@@ -9,7 +9,7 @@ Orchestrates tile downloading and persistence. Bridges the downloader (Google Ma
 
 ### TileService (implements ITileService)
 - `DownloadAndStoreTilesAsync(double lat, double lon, double sizeMeters, int zoomLevel, CancellationToken) → Task<List<TileMetadata>>`:
-  1. Queries existing tiles in the region from the repository (filtered to current year's version)
+  1. Queries existing tiles in the region from the repository (latest per `(latitude, longitude, zoom_level, tile_size_meters)` post-AZ-357)
   2. Calls `ISatelliteDownloader.GetTilesWithMetadataAsync` with existing tiles to skip
   3. Creates `TileEntity` for each newly downloaded tile and inserts via repository (upsert)
   4. Returns combined list of existing + new tile metadata
@@ -19,10 +19,9 @@ Orchestrates tile downloading and persistence. Bridges the downloader (Google Ma
 - `DownloadAndStoreSingleTileAsync(double latitude, double longitude, int zoomLevel, CancellationToken) → Task<TileMetadata>` (AZ-311): download one tile by lat/lon, persist, return metadata
 
 ## Internal Logic
-- Version is `DateTime.UtcNow.Year` — tiles are considered fresh for the current calendar year
+- New rows write `Version = null` and `MapsVersion = null` (post-AZ-357 / AZ-373); the `version` and `maps_version` columns are retained for backward compatibility with pre-existing rows
-- `MapToMetadata(TileEntity) → TileMetadata`: entity-to-DTO mapping (static helper)
+- `MapToMetadata(TileEntity) → TileMetadata`: entity-to-DTO mapping (static helper); `MapsVersion` is no longer projected onto `TileMetadata` / `DownloadTileResponse`
-- Tile size hardcoded to 256 pixels, image type "jpg"
+- `TileSizePixels` sourced from `MapConfig.TileSizePixels` (default 256, post-AZ-371); image type fixed at `"jpg"`
-- `MapsVersion` formatted as `"downloaded_{date}"`
 - `IMemoryCache` keyed by `(z, x, y)` with 1h absolute / 30min sliding expiration; populated on first hit and on downloader fallback
 
 ## Dependencies