Promotes 8 operational levers into config keys with defaults that match
the prior source literals byte-for-byte:
ProcessingConfig: RegionProcessingTimeoutSeconds (300),
RouteProcessingPollIntervalSeconds (5),
MaxRoutePointSpacingMeters (200), LatLonTolerance (0.0001).
MapConfig: TileSizePixels (256), AllowedZoomLevels ([15..19]),
RetryBaseDelaySeconds (1), RetryMaxDelaySeconds (30).
Sites updated: RegionService, RouteProcessingService,
RoutePointGraphBuilder, RouteValidator, RouteService 4-arg ctor,
RouteImageRenderer, GoogleMapsDownloaderV2, TileService. Closes LF-2 by
forwarding HttpContext.RequestAborted from GetTileByLatLon into the
downloader. appsettings.json gains the 8 new keys at default values.
Tests: 141 / 141 unit + 5 / 5 smoke green. New ConfigDefaultsTests pins
defaults to original literals; new TileService unit test asserts CT
identity from caller to downloader (AZ-371 AC-3).
Co-authored-by: Cursor <cursoragent@cursor.com>
Extract RouteValidator (aggregating validator), RoutePointGraphBuilder
(point interpolation + sequence numbering), GeofenceGridCalculator
(NW/SE region centers), and RouteResponseMapper (entity -> DTO; also
used by GetRouteAsync, eliminating duplicate DTO assembly).
CreateRouteAsync shrinks 184 -> 52 LOC of orchestration. RouteService.cs
shrinks 295 -> 138 LOC overall. Validation aggregates all failures into
a single ArgumentException (AC-2); single-violation messages preserved
verbatim so existing RouteServiceTests pass unchanged. 28 new unit
tests for the four helpers (112/112 unit tests, smoke green).
Co-authored-by: Cursor <cursoragent@cursor.com>