[AZ-376] [AZ-378] [AZ-379] [AZ-380] Repo cleanup: dead code, logger discipline, ColumnList consts

Batch 23 of refactor 03-code-quality-refactoring (4 tasks, 5 SP):

- AZ-376 (C23): Delete unused FindExistingTileAsync from
  ITileRepository / TileRepository. No callers; method also took the
  obsolete `version` arg removed by C06/AZ-357.
- AZ-378 (C25): Repository _logger discipline.
  TileRepository.GetTilesByRegionAsync now emits LogWarning when the
  query exceeds SlowQueryThresholdMs (500 ms). RegionRepository and
  RouteRepository drop the unused ILogger<TRepo> field, parameter, and
  using; Program.cs DI registrations updated.
- AZ-379 (C26): Extract `private const string ColumnList` per repo
  (TileRepository, RegionRepository, RouteRepository); SELECTs use
  $@"SELECT {ColumnList} FROM ..." (C# 10+ const interpolation).
  INSERT/UPDATE/DELETE unchanged; route_points single-site SELECT left
  inline.
- AZ-380 (C27): Delete dead alias GeoUtils.CalculatePolygonDiagonalDistance.

Tests: +9 new (RepositoryRefactorTests x8, GeoUtilsRefactorTests x1)
covering each AC via reflection / file-content assertions; pattern
mirrors ToolingConfigurationTests (b22) and AcceptanceCriteriaRT2Tests
(b19). Unit suite 181 -> 190, all green. dotnet format clean.

Code review: PASS_WITH_WARNINGS (3 Low findings, all informational or
out-of-scope for this batch). See
_docs/03_implementation/reviews/batch_23_review.md.

Cumulative review counter 2/3; next K=3 review fires after batch 24.

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

SatelliteProvider.DataAccess/Repositories/TileRepository.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics;
 using Dapper;
 using Microsoft.Extensions.Logging;
 using Npgsql;
@@ -7,6 +8,14 @@ namespace SatelliteProvider.DataAccess.Repositories;
 
 public class TileRepository : ITileRepository
 {
+    private const int SlowQueryThresholdMs = 500;
+
+    private const string ColumnList = @"id, tile_zoom as TileZoom, tile_x as TileX, tile_y as TileY,
+                   latitude, longitude,
+                   tile_size_meters as TileSizeMeters, tile_size_pixels as TileSizePixels,
+                   image_type as ImageType, maps_version as MapsVersion, version,
+                   file_path as FilePath, created_at as CreatedAt, updated_at as UpdatedAt";
+
     private readonly string _connectionString;
     private readonly ILogger<TileRepository> _logger;
 
@@ -19,13 +28,9 @@ public class TileRepository : ITileRepository
     public async Task<TileEntity?> GetByIdAsync(Guid id)
     {
         using var connection = new NpgsqlConnection(_connectionString);
-        const string sql = @"
-            SELECT id, tile_zoom as TileZoom, tile_x as TileX, tile_y as TileY,
-                   latitude, longitude, 
-                   tile_size_meters as TileSizeMeters, tile_size_pixels as TileSizePixels,
-                   image_type as ImageType, maps_version as MapsVersion, version,
-                   file_path as FilePath, created_at as CreatedAt, updated_at as UpdatedAt
-            FROM tiles 
+        const string sql = $@"
+            SELECT {ColumnList}
+            FROM tiles
             WHERE id = @Id";
 
         return await connection.QuerySingleOrDefaultAsync<TileEntity>(sql, new { Id = id });
@@ -34,13 +39,9 @@ public class TileRepository : ITileRepository
     public async Task<TileEntity?> GetByTileCoordinatesAsync(int tileZoom, int tileX, int tileY)
     {
         using var connection = new NpgsqlConnection(_connectionString);
-        const string sql = @"
-            SELECT id, tile_zoom as TileZoom, tile_x as TileX, tile_y as TileY,
-                   latitude, longitude,
-                   tile_size_meters as TileSizeMeters, tile_size_pixels as TileSizePixels,
-                   image_type as ImageType, maps_version as MapsVersion, version,
-                   file_path as FilePath, created_at as CreatedAt, updated_at as UpdatedAt
-            FROM tiles 
+        const string sql = $@"
+            SELECT {ColumnList}
+            FROM tiles
             WHERE tile_zoom = @TileZoom AND tile_x = @TileX AND tile_y = @TileY
             ORDER BY updated_at DESC
             LIMIT 1";
@@ -48,33 +49,6 @@ public class TileRepository : ITileRepository
         return await connection.QuerySingleOrDefaultAsync<TileEntity>(sql, new { TileZoom = tileZoom, TileX = tileX, TileY = tileY });
     }
 
-    public async Task<TileEntity?> FindExistingTileAsync(double latitude, double longitude, double tileSizeMeters, int zoomLevel, int version)
-    {
-        using var connection = new NpgsqlConnection(_connectionString);
-        const string sql = @"
-            SELECT id, tile_zoom as TileZoom, tile_x as TileX, tile_y as TileY,
-                   latitude, longitude, 
-                   tile_size_meters as TileSizeMeters, tile_size_pixels as TileSizePixels,
-                   image_type as ImageType, maps_version as MapsVersion, version,
-                   file_path as FilePath, created_at as CreatedAt, updated_at as UpdatedAt
-            FROM tiles 
-            WHERE ABS(latitude - @Latitude) < 0.0001 
-              AND ABS(longitude - @Longitude) < 0.0001 
-              AND ABS(tile_size_meters - @TileSizeMeters) < 1
-              AND tile_zoom = @TileZoom
-              AND version = @Version
-            LIMIT 1";
-
-        return await connection.QuerySingleOrDefaultAsync<TileEntity>(sql, new
-        {
-            Latitude = latitude,
-            Longitude = longitude,
-            TileSizeMeters = tileSizeMeters,
-            TileZoom = zoomLevel,
-            Version = version
-        });
-    }
-
     public async Task<IEnumerable<TileEntity>> GetTilesByRegionAsync(double latitude, double longitude, double sizeMeters, int zoomLevel)
     {
         using var connection = new NpgsqlConnection(_connectionString);
@@ -90,19 +64,16 @@ public class TileRepository : ITileRepository
         var latRange = expandedSizeMeters / 111000.0;
         var lonRange = expandedSizeMeters / (111000.0 * Math.Cos(latitude * Math.PI / 180.0));
 
-        const string sql = @"
-            SELECT id, tile_zoom as TileZoom, tile_x as TileX, tile_y as TileY,
-                   latitude, longitude, 
-                   tile_size_meters as TileSizeMeters, tile_size_pixels as TileSizePixels,
-                   image_type as ImageType, maps_version as MapsVersion, version,
-                   file_path as FilePath, created_at as CreatedAt, updated_at as UpdatedAt
-            FROM tiles 
+        const string sql = $@"
+            SELECT {ColumnList}
+            FROM tiles
             WHERE latitude BETWEEN @MinLat AND @MaxLat
               AND longitude BETWEEN @MinLon AND @MaxLon
               AND tile_zoom = @TileZoom
             ORDER BY latitude DESC, longitude ASC, updated_at DESC";
 
-        return await connection.QueryAsync<TileEntity>(sql, new
+        var stopwatch = Stopwatch.StartNew();
+        var tiles = await connection.QueryAsync<TileEntity>(sql, new
         {
             MinLat = latitude - latRange / 2,
             MaxLat = latitude + latRange / 2,
@@ -110,6 +81,16 @@ public class TileRepository : ITileRepository
             MaxLon = longitude + lonRange / 2,
             TileZoom = zoomLevel
         });
+        stopwatch.Stop();
+
+        if (stopwatch.ElapsedMilliseconds > SlowQueryThresholdMs)
+        {
+            _logger.LogWarning(
+                "Slow GetTilesByRegionAsync: {ElapsedMs} ms (threshold {ThresholdMs} ms) for lat={Latitude}, lon={Longitude}, sizeMeters={SizeMeters}, zoom={ZoomLevel}",
+                stopwatch.ElapsedMilliseconds, SlowQueryThresholdMs, latitude, longitude, sizeMeters, zoomLevel);
+        }
+
+        return tiles;
     }
 
     public async Task<Guid> InsertAsync(TileEntity tile)