[AZ-808] [AZ-811] Strict validation on region POST + lat/lon GET

AZ-808: FluentValidation for POST /api/satellite/request
- RegionRequestValidator: id non-empty, lat/lon/sizeMeters/zoomLevel ranges
- RequestRegionRequest: [JsonRequired] on every property, no implicit defaults
- Wired via .WithValidation<RequestRegionRequest>() in MapPost chain
- Unit + integration tests + curl probe script
- New contract: contracts/api/region-request.md v1.0.0

AZ-811: FluentValidation + envelope filter for GET /api/satellite/tiles/latlon
- GetTileByLatLonQuery: nullable record (double?/int?) so the minimal-API
  binder never short-circuits with BadHttpRequestException before filters
- GetTileByLatLonQueryValidator: Cascade(Stop) + NotNull + InclusiveBetween
  per param; missing surfaces as `\`<name>\` is required.`
- RejectUnknownQueryParamsEndpointFilter: reusable IEndpointFilter that
  rejects any query key outside the allowed set with errors[<key>] map;
  catches legacy `?Latitude=` typos and hostile probes (`?debug=1&admin=1`)
- Handler: [AsParameters] GetTileByLatLonQuery + .Value deref post-validator
- Unit (validator + filter) + integration tests + curl probe script
- New contract: contracts/api/tile-latlon.md v1.0.0

Shared hygiene
- Promote AssertErrorsContainsMention from per-test-file private helpers to
  ProblemDetailsAssertions (closes batch-1 Low-severity DRY warning)
- Sync Swagger param descriptions, README, blackbox/security/perf scripts,
  uuidv5 doc with the new lat/lon/zoom query-param names

Docs
- system-flows.md F1/F2 reference the new contracts + validation layers
- modules/api_program.md adds Api/Validators + Api/DTOs sections
- _autodev_state.md: batch 2 of 4 complete; next batch = AZ-809

All smoke tests green (mode=smoke, exit 0). AZ-808 + AZ-811 transitioned
to In Testing on Jira.

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

_docs/02_document/tests/blackbox-tests.md

@@ -2,7 +2,7 @@
 
 ## BT-01: Single Tile Download
 
-**Trigger**: GET /api/satellite/tiles/latlon?Latitude=47.461747&Longitude=37.647063&ZoomLevel=18
+**Trigger**: GET /api/satellite/tiles/latlon?lat=47.461747&lon=37.647063&zoom=18
 **Precondition**: Tile not in cache
 **Expected**: HTTP 200; JSON with zoomLevel=18, tileSizePixels=256, imageType="jpg", filePath matching pattern `tiles/18/*/...`
 **Pass criterion**: All fields present and correct values
@@ -86,13 +86,13 @@
 
 ## BT-N01: Invalid Coordinates (out of range)
 
-**Trigger**: GET /api/satellite/tiles/latlon?Latitude=91&Longitude=181&ZoomLevel=18
+**Trigger**: GET /api/satellite/tiles/latlon?lat=91&lon=181&zoom=18
 **Expected**: Error response
 **Pass criterion**: HTTP 4xx or error in response body
 
 ## BT-N02: Invalid Zoom Level
 
-**Trigger**: GET /api/satellite/tiles/latlon?Latitude=47.46&Longitude=37.64&ZoomLevel=25
+**Trigger**: GET /api/satellite/tiles/latlon?lat=47.46&lon=37.64&zoom=25
 **Expected**: Error response
 **Pass criterion**: HTTP 4xx or error indicating invalid zoom
 
@@ -163,7 +163,7 @@ All Cycle-2 UAV scenarios run with a JWT containing `permissions: ["GPS"]` (per
 
 ## BT-18: Existing Tile Endpoint Returns Identical Body with Valid Bearer
 
-**Trigger**: GET `/api/satellite/tiles/latlon?Latitude=47.461747&Longitude=37.647063&ZoomLevel=18` with a valid Bearer token.
+**Trigger**: GET `/api/satellite/tiles/latlon?lat=47.461747&lon=37.647063&zoom=18` with a valid Bearer token.
 **Precondition**: Tile may or may not be cached.
 **Expected**: Response body is structurally identical to BT-01 (`tileId`, `zoomLevel == 18`, `tileSizePixels == 256`, `imageType == "jpg"`, `filePath` matches `tiles/18/*/*`).
 **Pass criterion**: status == 200 AND BT-01's pass criterion AND no behavioral change vs pre-AZ-487 baseline.