unworked validation sweep: tick task-047/048/049/052 minor backlog

All minor findings in task-047, task-048, task-049, and both task-052
sweep files already carry explicit *Status:* annotations
(wontfix / deferred / fixed-in-iter1-batch) recorded by the iter1
fix-cleanup commits. This commit just ticks their checkboxes so the
backlog summary reflects reality.

Also compacted the 2026-05-27_000000_task-052.md iter0 file: every item
in it is a 1:1 duplicate of an item in the iter1 file
(2026-05-27_010619_task-052.md), so the iter0 file now carries only a
cross-walk table pointing at the iter1 dispositions.

Added top-of-file sweep-status banners to task-047/048 for at-a-glance
context, matching the format used on task-053..057.

No code changes — this is purely backlog bookkeeping.

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

Author: etr