TASK-040: record unworked validation findings (1 major, 81 minor)

Snapshot of the final validation-loop report — one major and 81 minor
items that were knowingly left for follow-up (cosmetic style nits,
documentation-only examples, ergonomic improvements to the verify
script, and a single architecture finding on
empty_response_example.cpp where the example exposes
`MHD_RF_HEAD_ONLY_RESPONSE`; addressing it cleanly requires a
libhttpserver-native HEAD-only flag that does not yet exist in the
public API). No criticals.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: etr