chore: replace redis with valkey

[gustavosbarreto]

What

Swaps the Redis container image for Valkey across
the compose files and the asynq test containers.

Where	Before	After
docker-compose.yml	redis	valkey/valkey:8.1
docker-compose.enterprise.yml	cache/redis	cache/valkey/valkey:8.1
pkg/worker/asynq/{client,server}_test.go	docker.io/redis:7	docker.io/valkey/valkey:8.1

Why

Redis moved to SSPL/RSALv2 in 2024 and AGPLv3 in 2025. Valkey is the
BSD-3 fork maintained by the Linux Foundation and is a drop-in
replacement: same RESP protocol, same clients.

No Go code changes. The go-redis/asynq clients, the redis:// URIs,
and the redis service name are kept as-is to minimize churn. The
testcontainers redis module boots the Valkey image fine since its wait
strategy matches Valkey's Ready to accept connections log line.

Note

The enterprise registry path cache/valkey/valkey assumes the
pull-through cache mirrors the upstream valkey/valkey image. Worth
confirming it resolves before merge.

[github-actions]

Claude finished @gustavosbarreto's task in 4m 2s —— View job

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Code Review Complete

Reviewed 4 files across code quality, security, testing, Go patterns, and architecture — no issues found. The change is a clean, consistent swap of Redis container images to Valkey 8.1 across all relevant locations:

• docker-compose.yml — image and server command updated correctly
• docker-compose.enterprise.yml — mirrors the upstream valkey/valkey namespace through the pull-through cache
• Test containers in pkg/worker/asynq/ — both updated to match

Cross-repo check confirmed the cloud repo's compose files don't define their own redis service (they overlay the base), so no changes needed there. No stale redis-server or docker.io/redis references remain anywhere in the codebase.

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