[rennf93]

Security fix for GHSA-c9ww-6vhw-667p, shipping in 4.4.0.

scan_request ended the request scan as clean on a value that was a threat but had no reportable category: a value whose threats were all filtered out (a disabled category, a header skip set) returned an empty verdict immediately, so a later query, header or body value carrying an enabled attack was never scanned, and a semantic-only threat was never reported. A value none of whose threats is reportable is now treated as a miss and the scan continues, as the reference _check_value_enhanced does. Semantic threats report their attack type as the category and a threat with no threats list reports as uncategorized. The conformance pipeline runner follows the same rule.

Probe tests in detection_exclusions cover a filtered-out value followed by an attack, a disabled category, a semantic-only value, and the uncategorized case. The CHANGELOG 4.4.0 section notes the fix and the category-list change.