fix(revoke): retry wording and lock time after an uncertain Azure Return #1584

Since #1579, an ambiguous Azure Return failure keeps the in-flight flag, and the 2h sweep releases it. Two user-facing gaps remain:

1. Retry wording. A retry while the outcome is uncertain gets the existing 207 RECONCILE_PENDING "Refund already issued ... Do not retry". The refund may not have happened, so the message should say the outcome is uncertain and to check the Azure portal.
2. Lock time and the single-send refusal. The flag can lock the purchase for up to 2h, which can run past the 7-day free-cancel window. After the release, a new revoke can get Azure's "already returned" 4xx on a single send. That clears the flag and leaves a refunded purchase showing as active, as on main before fix(revoke): keep the in-flight flag on an ambiguous Azure Return failure and refuse a late Lambda claim #1579. Consider mapping Azure's "already returned" error code to revoked rather than to a definite refusal.

Found by both independent reviews of #1579.