[ewlarson]

OGC search responses could return features while reporting zero matches, emit query duration as timeStamp, and fail response validation when a record description was an empty list. This fixes projection against the actual search and native detail response shapes, including sparse metadata, geometry, pagination, and public links.

Bounding boxes now select intersecting record extents without the native map overlap threshold, including antimeridian crossings. Unsupported filters and sorts return explicit errors. Discovery and media types reflect the implemented behavior, and unverified conformance claims are removed; this remains a partial OGC Records facade.

Closes #480.

Validation

• Full backend lint and format checks passed.
• Full backend suite: 2,268 passed, 135 skipped, 1 xpassed.
• Focused OGC and error-contract suite: 90 passed.
• Exact empty-description regression at feature index 1 and related sparse-input cases rerun: 6 passed.
• Live local Elasticsearch checks passed for extent intersection, edge contact, and narrow/wide antimeridian boxes; temporary test index removed.

The initial full-suite run lacked boto3; it passed after supplying the dependency in a temporary test directory. Coverage thresholds and a formal OGC conformance suite were not run. Temporal and identifier filters, full sorting semantics, and remaining Records requirements remain future work.