Astra: L18 joint round, round 4 (confirming)

Round 3 (CODEX-REVIEW-L18-JOINT-ROUND-FINAL-3.md) left one item open: finding 1, where moves' restoring phase lost the source's files protection. You approved the fix on static review (moves a5e8c13f).

Since then:

1. Fix merged to main as 650e6152. It is the squash of a5e8c13f, and CI was green on that tip. The build branch region-ha-1b-next-build now has main merged in, at the commit under review. Main also brought in unrelated work (release, update target, updatewords and more), 134 files in all.
2. Model aligned (region-ha-two-box-build at eaa08175). - The source region stays the files home through releasing and released, until the source's return. - After a dirty return, until the source's probe is admitted, the source is no longer the files home. The D6 install park then retires the pre-move generations. - INV-30 does not count those generations in that window. - The new test TestDirtyReturnParksPreMoveFiles fails under the files-home-move-phases mutation. - The unmutated 3000-seed two-box run had no failures.

Judge:

1. Is finding 1 closed in the merged build (internal/host/movessources.go, and its callers in the merged tree)?
2. Does the model at eaa08175 match the code's restoring and D6 behaviour?
3. Did merging main into the relocation branch (8ad2c570) break anything relocation depends on? In particular, check: - the completion barrier (RelocationStartGuard, StartGuard, completionBarrier); - EndProbe and flushStopped; - completionFence and BeginPurge's fencedCompletion; - the census and copy gates.
4. Verdict: may relocation merge dormant?

Give findings P1/P2/P3 with file:line. Report only new items; do not re-litigate settled rulings.