Update integration tests for the AOI builder request/result API

[sdrichards-bc]

Summary

Update integration-test AOI construction to use the new AOIBuilder API. The shared AOI fixture and KML reprojection test now create an AOIBuildRequest, call build_from_request(), and extract the AreaOfInterest from the returned build result.

This restores compatibility between integration-test setup and the updated AOI builder, allowing the file pipeline tests to exercise the current application API.

Changes

• Import AOIBuildRequest at both AOI construction sites.
• Wrap the existing AOIRequest and source GeoDataFrame in AOIBuildRequest(spec=request, raw_gdf=...).
• Build the AOI through AOIBuilder().build_from_request(build_request).
• Use built_aoi.aoi wherever the fixture or pipeline requires an AreaOfInterest.

File	Update
conftest.py	Migrate the shared, session-scoped aoi fixture to the new builder boundary while continuing to return an AreaOfInterest.
test_file_pipeline.py	Migrate AOI construction in test_kml_aoi_reprojects() and pass the extracted AOI to run_analysis().

Dependency

Requires pr/aoi-builder update that introduces AOIBuildRequest, build_from_request(), and AOIBuildResult. Merge this after that update, or target its branch while reviewing the changes together.

Check List

• [Y] Code runs locally
• [N] Tests pass
• [Y] New behavior has tests
• [Y] Documentation updated if behavior changed
• [Y] No secrets, credentials, or local-only paths committed
• [Y] Logging uses module-level loggers
• [Y] Exceptions and validation results follow engine convention