chore(scripts): index scripts/ and archive 29 one-shot scripts
backlog#1153 infra-13. scripts/ had 80+ unlabelled top-level entries
mixing CI gates with finished one-shot issue-validation scripts.
- scripts/README.md — one index row per entry with status
(ci-gate / dev-tool / archived), purpose, and wiring; subdirectories
get one row each. run_scanner_benchmarks.sh is annotated
"disposition owned by backlog perf-10" and deliberately untouched.
- git mv 29 confirmed-stale one-shot entries to scripts/archive/:
11 issue-scoped validation/perf-capture scripts, the 5-script
backlog#706 large-PUT breakdown family, the 4-file GET-optimization
stress suite, 2 gt1g one-shots, and 7 other orphaned one-shots.
Evidence: a whole-tree boundary-aware reference census showed zero
references from CI/Makefiles/docs/code for every moved entry (or
references only from other scripts inside the same archived set);
re-run after the move shows zero dangling references.
- docs/testing/README.md links the index.
Moves only — no script content changed.
Zhengchao An