feat(events): add Ledger v3 broker schemas

[flemzord]

Summary

• add schemas for every Ledger v3 event currently emitted by the event sink to NATS and Kafka
• model the Ledger v3 envelope as type, ledger, date, logSequence, and the complete log
• support version-specific event envelopes while preserving the historical Stack payload envelope
• keep legacy Ledger event lookup working for event types that only exist in v1/v2
• regenerate both canonical and legacy event catalogues

Ledger v3 events

• COMMITTED_TRANSACTION
• REVERTED_TRANSACTION
• SAVED_METADATA
• DELETED_METADATA
• CREATED_LEDGER
• DELETED_LEDGER
• SKIPPED_ORDER

Validation

• cd events && go test ./...
• cd events && go vet ./...
• nix develop -c just generate-events
• Ledger release/v3.0 targeted event conversion and JSON serialization tests
• exact comparison between the Ledger EventType enum and the generated v3 catalogue
• generated catalogue reproducibility and canonical/legacy checksum equality
• git diff --check

Notes

The schemas are based on the current formancehq/ledger release/v3.0 sink serialization. NATS and Kafka share the same serialized event envelope; only transport routing differs.

[NumaryBot]

✅ Approve — automated review

No actionable correctness issues were identified in the current diff.

No findings.