PR #2151 added deleteOrphanProcessingClaims() to resetStuckProcessingRows(), but outDb is always opened readonly (openOutboundDb uses immutable: true). The write silently failed, leaving orphan processing_ack rows that block future message delivery for the session. Fix: add openOutboundDbRw() alongside the existing readonly opener and use it in resetStuckProcessingRows() to open a short-lived writable handle just for the delete. The readonly handle is still used for all reads above. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>