Improve test coverage for kafka-queue package (1 active test, 1251 LOC)

[BrewingCoder]

Area

Backend — Worker / Kafka

Category

Test coverage

Description

The kafka-queue package handles all async data ingestion (sessions, errors, logs, traces, metrics) but has only 1 enabled test (partition key hash). The integration test (TestQueue_Submit) is skipped by default.

Priority test targets:

1. Message serialization/deserialization round-trip for all 20+ payload types
2. Topic name generation with env prefixes
3. OTel context injection/extraction via Kafka headers
4. Config override behavior (batch size, message size, async mode)
5. deserializeMessage() type dispatch (peek at Type field, allocate concrete struct)

Known risks:

• No retry logic (TaskRetries=0) — failed messages are dropped
• Background stats goroutine never cleaned up on shutdown
• Deprecated HubSpot enum values (12-16) still in type list

See src/backend/kafka-queue/MODULE.md for full analysis.

Affected Files / Packages

src/backend/kafka-queue/kafkaqueue.go (578 lines)
src/backend/kafka-queue/types.go (427 lines)
src/backend/kafka-queue/kafkaqueue_test.go (159 lines — 1 active test)

[github-actions]

AI Triage: Improve test coverage for kafka-queue package which currently has only 1 enabled test despite handling all async data ingestion with significant untested code paths and known risks.

Labels applied: area:backend, tech-debt, priority:medium, component:database