TASK-074: mark Done in M7 milestone index and persist unworked review issues

Mark TASK-074 status as Done in the task file and milestone index, and
record the 28 review findings (6 major, 22 minor) that were not actioned
during this task so they can be picked up by a follow-up cleanup pass.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: etr

specs/tasks/M7-v2-cleanup/TASK-074.md

@@ -27,4 +27,4 @@
 **Related Requirements:** PRD §2 security NFR (defense-in-depth)
 **Related Decisions:** None new
 
-**Status:** In Progress
+**Status:** Done

specs/tasks/M7-v2-cleanup/_index.md

@@ -38,7 +38,7 @@ TASK-093).
 | TASK-071 | Wire `install_not_found_alias_` stub and remove dead `lambda_handler` arm | MED | S | Done |
 | TASK-072 | Arena-allocated unescape on the warm path | MED | M | Done |
 | TASK-073 | Revisit libmicrohttpd v0.99 unescape workaround | LOW | S | Done |
-| TASK-074 | Gate DEBUG raw-body printing behind explicit opt-in | LOW (sec) | S | Backlog |
+| TASK-074 | Gate DEBUG raw-body printing behind explicit opt-in | LOW (sec) | S | Done |
 | TASK-075 | Propagate `wait_for_server_ready` to sibling hooks integ tests | HIGH | M | Backlog |
 | TASK-076 | Replace tautological-pass blocks in TLS test lanes | HIGH | M | Backlog |
 | TASK-077 | Restore Windows / Darwin coverage in skipped test suites | HIGH | L | Backlog |