fix(s3api): clear stale object lock years (#9890)

Problem: Re-storing object-lock default retention with Days left a previous Years extended attribute in place, so later loads could see both Days and stale Years.

Root cause: StoreObjectLockConfigurationInExtended only wrote period fields that were set on the new configuration and did not delete old Days or Years keys before writing the replacement rule.

Fix: Clear stored default-retention Days and Years keys before writing the current default retention period fields.

Reproduction: go test ./weed/s3api -run TestStoreObjectLockConfigurationClearsStaleYears -count=1 failed before the fix because the stale years key remained.

Validation: go test ./weed/s3api -run TestStoreObjectLockConfigurationClearsStaleYears -count=1; go test ./weed/s3api -count=1; git diff --check; git diff --cached --check

Co-authored-by: Codex <noreply@openai.com>

weed/s3api/object_lock_utils.go

@@ -95,6 +95,9 @@ func StoreObjectLockConfigurationInExtended(entry *filer_pb.Entry, config *Objec
 	if config.Rule != nil && config.Rule.DefaultRetention != nil {
 		defaultRetention := config.Rule.DefaultRetention
 
+		delete(entry.Extended, s3_constants.ExtObjectLockDefaultDaysKey)
+		delete(entry.Extended, s3_constants.ExtObjectLockDefaultYearsKey)
+
 		// Store mode
 		if defaultRetention.Mode != "" {
 			entry.Extended[s3_constants.ExtObjectLockDefaultModeKey] = []byte(defaultRetention.Mode)