Consume events from the topic exchange

[Uxío (Uxio0)]

Make sure these boxes are checked! 📦✅

• You ran ./run_tests.sh
• You ran pre-commit run -a

What was wrong? 👾

Closes PLA-2114

Decoder Service consumes from the legacy fanout exchange safe-transaction-service-events, which is going to be removed from Transaction Service (PLA-2111).

How was it fixed? 🎯

• RABBITMQ_AMQP_EXCHANGE default is now safe-transaction-service-events-with-topics. The exchange is declared as durable topic, the same as Transaction Service.
• The queue is bound only with *.EXECUTED_MULTISIG_TRANSACTION.*, the one type the service processes. The type lives in CONSUMED_EVENT_TYPES, used by both the binding and EventsService._is_processable_event.
• Tests against a real RabbitMQ: a bound type reaches the queue, unbound types (e.g. INCOMING_ETHER) do not.

Notes:

• Existing queues keep their old binding to the fanout. RabbitMQ delivers a message to a queue only once even if two bindings match, and the binding is deleted together with the fanout exchange (PLA-2111). Until then the queue still gets every event through the fanout, so the narrowing has effect after PLA-2111.
• Any environment that sets RABBITMQ_AMQP_EXCHANGE=safe-transaction-service-events must change or remove it, or startup fails with PRECONDITION_FAILED.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-06T16:08:41.905321Z	84c52f7	Draft marked ready

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