docs(qa): rewrite cli.migrate-meta-codemod to the contract os migrate meta ships (#9733) (#10412)

The item was `active` P1 asserting an in-place source codemod. The command
declares from/to/step/out/stored/database-url/apply/yes/force/type/json — no
--write/--fix — and the authored-source arm's only file write is the --out
JSON snapshot; meta.ts's header calls the AST rewrite "unsafe and lossy". Its
grep step also targeted a sentence #9529 withdrew, so it could not run.

Rewritten clause-for-clause to what is real today (printed mechanical-edit
list, sources provably untouched, schema-valid --out snapshot, idempotent
replay, floor refusal, semantic advisories, --json exit honesty) and kept
active/P1 rather than retired — the defect was in the item, not in coverage.
The v18 rewrite half stays on #9591; the restart is mechanical here, as a
--help flag-surface check that fires when --write appears.


Claude-Session: https://claude.ai/code/session_01DdCnBGcHeufjrq7drTD3wt

Co-authored-by: Claude <noreply@anthropic.com>

Author: os-zhuang