[AZ-284] Autodev baseline + testability refactor

Phase A baseline outputs from /autodev (Steps 1-5):
- Problem & solution docs (_docs/00_problem, _docs/01_solution)
- Codebase documentation (_docs/02_document) incl. architecture,
  module-layout, glossary, system-flows, baseline compliance scan
- Test specs (blackbox, performance, resilience, security, resource,
  traceability matrix)
- Test task decomposition (_docs/02_tasks/todo): AZ-285..AZ-290
- Testability refactor (_docs/04_refactoring/01-testability-refactoring):
  - TC-01 Move DownloadedTileInfoV2 + new ExistingTileInfo to Common.DTO
  - TC-02 Replace dead ISatelliteDownloader API with real signatures
  - TC-03 GoogleMapsDownloaderV2 implements ISatelliteDownloader
  - TC-04 TileService depends on ISatelliteDownloader (mockable)
  - TC-05 DI + endpoints use ISatelliteDownloader
- Test runner scripts (scripts/run-tests.sh, run-performance-tests.sh)
- Autodev state pointer (_docs/_autodev_state.md)

Prepares the codebase for AZ-285..AZ-290 unit/integration test work.

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

_docs/02_document/modules/common_dtos.md

@@ -0,0 +1,101 @@
+# Module: Common/DTO
+
+## Purpose
+Data transfer objects used across all layers — API requests/responses, inter-service communication, and queue messages.
+
+## Public Interface
+
+### GeoPoint
+Geographic coordinate with tolerance-based equality.
+- `Lat` (double): latitude, JSON property `"lat"`
+- `Lon` (double): longitude, JSON property `"lon"`
+- Constructor: `GeoPoint()`, `GeoPoint(double lat, double lon)`
+- Equality: two points are equal if both coordinates differ by less than `0.00005` (PRECISION_TOLERANCE)
+- Operator overloads: `==`, `!=`
+
+### Direction
+Result of a directional calculation between two points.
+- `Distance` (double): distance in meters
+- `Azimuth` (double): bearing in degrees (0–360)
+
+### SatTile
+Represents a single map tile with its spatial bounds.
+- `X`, `Y` (int): tile coordinates in the slippy map scheme
+- `Zoom` (int): zoom level
+- `LeftTop`, `BottomRight` (GeoPoint): computed bounding box corners (via `GeoUtils.TileToWorldPos`)
+- `Url` (string): download URL
+- `FileName → string`: formatted as `{X}.{Y}.{Zoom}.jpg`
+
+### TileMetadata
+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)
+- `CreatedAt`, `UpdatedAt` (DateTime)
+
+### RegionRequest
+Queue message for async region processing.
+- `Id` (Guid), `Latitude`, `Longitude` (double), `SizeMeters` (double)
+- `ZoomLevel` (int), `StitchTiles` (bool)
+
+### RegionStatus
+Response DTO for region status queries.
+- `Id` (Guid), `Status` (string), `CsvFilePath`, `SummaryFilePath` (string?)
+- `TilesDownloaded`, `TilesReused` (int), `CreatedAt`, `UpdatedAt` (DateTime)
+
+### RoutePoint
+Input point in a route creation request.
+- `Latitude` (double, JSON: `"lat"`), `Longitude` (double, JSON: `"lon"`)
+
+### RoutePointDto
+Output point in a route response (includes computed fields).
+- `Latitude`, `Longitude` (double), `PointType` (string: "start"/"end"/"action"/"intermediate")
+- `SequenceNumber`, `SegmentIndex` (int), `DistanceFromPrevious` (double?)
+
+### CreateRouteRequest
+API request body for route creation.
+- `Id` (Guid), `Name` (string), `Description` (string?)
+- `RegionSizeMeters` (double), `ZoomLevel` (int)
+- `Points` (List\<RoutePoint\>), `Geofences` (Geofences?)
+- `RequestMaps` (bool), `CreateTilesZip` (bool)
+
+### RouteResponse
+API response for route queries.
+- All fields from the route entity plus `Points` (List\<RoutePointDto\>)
+- `MapsReady` (bool), `TilesZipPath` (string?)
+
+### GeofencePolygon
+Axis-aligned bounding box defined by NW and SE corners.
+- `NorthWest` (GeoPoint?), `SouthEast` (GeoPoint?)
+
+### Geofences
+Container for multiple geofence polygons.
+- `Polygons` (List\<GeofencePolygon\>)
+
+## Internal Logic
+- `GeoPoint` uses a precision tolerance of `0.00005` degrees (~5.5 meters) for equality comparison.
+- `SatTile` eagerly computes its bounding box corners on construction by calling `GeoUtils.TileToWorldPos`.
+
+## Dependencies
+- `GeoPoint`, `Direction` — no imports
+- `SatTile` → `SatelliteProvider.Common.Utils.GeoUtils`
+- All others — no internal dependencies (or only `System.Text.Json.Serialization`)
+
+## Consumers
+- All services, repositories, and API endpoints consume these DTOs
+- `RegionRequest` is the message type for `IRegionRequestQueue`
+
+## Data Models
+These ARE the data models (DTOs). They map closely to the database entities but are decoupled from the persistence layer.
+
+## Configuration
+None consumed directly.
+
+## External Integrations
+None.
+
+## Security
+None.
+
+## Tests
+No dedicated DTO tests.