[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_tasks/todo/AZ-285_test_infrastructure.md

@@ -0,0 +1,30 @@
+# Test Infrastructure
+
+**Task**: AZ-285_test_infrastructure
+**Name**: Test Infrastructure: scaffold unit test project with mocks
+**Description**: Scaffold the unit test project with proper mocking infrastructure for ISatelliteDownloader and all repository interfaces
+**Complexity**: 3 points
+**Dependencies**: None
+**Component**: Blackbox Tests
+**Tracker**: AZ-285
+**Epic**: AZ-284
+
+## Scope
+
+- Replace DummyTest with actual test infrastructure in `SatelliteProvider.Tests`
+- Add Moq package for interface mocking (ISatelliteDownloader, ITileRepository, IRegionRepository, IRouteRepository, IRegionRequestQueue)
+- Add shared test fixtures with standard test coordinates (47.461747, 37.647063 for tiles; 48.276067, 37.384458 for routes)
+- Verify existing docker-compose.tests.yml works as integration test environment
+- Ensure FluentAssertions is available (already in project)
+
+## Test Project Layout
+
+Existing structure is sufficient — enhance `SatelliteProvider.Tests/`:
+- Add `Fixtures/` for shared test data
+- Add test classes per service (TileServiceTests, RegionServiceTests, RouteServiceTests)
+
+## Acceptance Criteria
+
+**AC-1**: Unit test project builds and all mock interfaces resolve
+**AC-2**: `docker-compose -f docker-compose.yml -f docker-compose.tests.yml up --build --abort-on-container-exit` succeeds
+**AC-3**: Test runner discovers and executes test classes