[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/components/05_route_management/description.md

@@ -0,0 +1,75 @@
+# RouteManagement
+
+## 1. High-Level Overview
+
+**Purpose**: Creates routes from user-defined waypoints, calculates intermediate points along the path, manages geofence regions, and generates consolidated route maps (stitched images, CSVs, summaries, ZIP archives) from completed region tile data.
+
+**Architectural Pattern**: Service + Background Poller
+
+**Upstream dependencies**: Common (DTOs, GeoUtils, configs), DataAccess (RouteRepository, RegionRepository), RegionProcessing (IRegionService for region creation)
+
+**Downstream consumers**: WebApi (CreateRoute/GetRoute endpoints)
+
+## 2. Internal Interfaces
+
+### Service: RouteService (implements IRouteService)
+See Common component for interface definition. Key implementation details:
+- `CreateRouteAsync`: validates, interpolates points every ≤200m, persists, creates geofence grid regions
+- `GetRouteAsync`: reads route + points from DB
+
+### BackgroundService: RouteProcessingService
+- `ExecuteAsync`: polls every 5 seconds for routes with `request_maps=true AND maps_ready=false`
+- `ProcessRouteSequentiallyAsync`: checks region completion, retries failed regions, generates maps when ready
+
+## 4. Data Access Patterns
+
+### Queries
+| Query | Frequency | Hot Path | Index Needed |
+|-------|-----------|----------|--------------|
+| GetRoutesWithPendingMapsAsync (polling) | Every 5s | No | `(request_maps, maps_ready)` |
+| GetRoutePointsAsync | Per route processing | Yes | `(route_id, sequence_number)` |
+| GetRegionIdsByRouteAsync | Per route processing | Yes | `(route_id)` |
+| InsertRoutePointsAsync (bulk) | Per route creation | No | — |
+
+## 5. Implementation Details
+
+**Algorithmic Complexity**: Point interpolation is O(n×m) where n = input points and m = max intermediate points per segment. Geofence grid creation is O(latSteps × lonSteps). Route-region matching uses O(points × regions) nearest-neighbor.
+
+**State Management**: Route state tracked in database (`request_maps`, `maps_ready` flags). Processing is polling-based (not queue-based like regions).
+
+**Key Dependencies**:
+| Library | Version | Purpose |
+|---------|---------|---------|
+| SixLabors.ImageSharp | 3.1.11 | Route map stitching with geofence borders and route markers |
+| System.IO.Compression | built-in | ZIP archive creation for tiles |
+
+**Error Handling**:
+- Route creation validates: min 2 points, size range, name required, geofence coordinate validity
+- RouteProcessingService catches exceptions per-route and continues to next
+- Failed regions are retried by creating new region requests
+- Tile coordinate extraction from filenames has a fallback returning (-1,-1) for unparseable names
+
+## 7. Caveats & Edge Cases
+
+- 200m max point spacing is hardcoded constant (`MAX_POINT_SPACING_METERS`)
+- Polling interval (5s) is hardcoded
+- `RouteProcessingService` resolves `IRegionService` via `IServiceProvider.CreateScope()` to avoid circular DI
+- Route map stitching extracts tile coordinates from filenames (`tile_{z}_{x}_{y}_{ts}.jpg`); format change would break stitching
+- ZIP creation runs on `Task.Run` (ThreadPool) — could consume a thread for large archives
+- `MatchRegionsToRoutePoints` uses O(n²) nearest-neighbor matching; could be slow for routes with many points
+- Region file cleanup deletes individual region CSVs/summaries after consolidation into route-level files
+- `catch` in `ExtractTileCoordinatesFromFilename` silently swallows all exceptions
+
+## 8. Dependency Graph
+
+**Must be implemented after**: Common, DataAccess, RegionProcessing
+**Can be implemented in parallel with**: nothing
+**Blocks**: nothing (top of the dependency chain alongside WebApi)
+
+## 9. Logging Strategy
+
+| Log Level | When | Example |
+|-----------|------|---------|
+| ERROR | Route processing failure | `Error processing route {RouteId}` |
+| WARN | Missing tile files, route not found, parse failures | `Tile file not found: {FilePath}` |
+| INFO | Processing complete, CSV/summary/zip generated | `Route {RouteId} maps processing completed` |