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>
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