[HLR] bsv-wallet-redis: Zero-to-running developer experience

[sgbett]

Problem

bsv-wallet-redis (#475) will be a new gem requiring Redis (and likely Sidekiq) as external infrastructure. Like bsv-wallet-postgres before #616, the DX risk is that developers install the gem and have no clear path to a working setup. Redis + Sidekiq is even more configuration-surface than Postgres alone (Redis server, Sidekiq process, connection URLs, queue names).

Acceptance criteria

Environment configuration

• .env.example documenting minimum required ENV vars (REDIS_URL at minimum, Sidekiq-specific vars if needed)
• The gem reads all configuration from ENV — no hardcoded connection strings

Docker setup

• docker-compose.yml providing Redis (and optionally a Sidekiq worker process)
• Non-ephemeral storage — Redis data directory mounted as a volume if persistence is required (RDB/AOF)
• If Sidekiq is included: worker process defined in compose, auto-starts with the correct queues

Documentation

• gem/bsv-wallet-redis/README.md — complete getting-started guide:
  • Install the gem
  • Copy .env.example to .env, fill in REDIS_URL
  • docker compose up -d for Redis (+ Sidekiq if applicable)
  • Ruby snippet: create a wallet client with Redis adapter in < 10 lines
  • Run the test suite against it
• docs/gems/bsv-wallet-redis.md — same content, integrated into project docs

Out-of-the-box experience

• Semi-competent developer goes from gem install bsv-wallet-redis to a working Redis-backed wallet component with a few commands in under a minute
• Sensible defaults for local development (localhost:6379, default database, no auth)
• Production guidance (AUTH, TLS, Sentinel/Cluster) is separate from getting-started

Context

• Sub-issue of [HLR] bsv-wallet-redis gem — Redis storage engine and Sidekiq broadcast adapter #475 (bsv-wallet-redis gem)
• Mirrors [HLR] bsv-wallet-postgres: Zero-to-running developer experience #616 (bsv-wallet-postgres DX) — same principles, different infrastructure
• The .env.example + Docker + README pattern should be consistent across all infrastructure-dependent gems
• Redis DX is arguably simpler than Postgres (no schema migration step) but Sidekiq adds its own setup surface

[sgbett]

Closing as not planned.

Companion to #475 — both Redis-storage HLRs are dropped because the wallet (now in the standalone bsv-wallet gem) settled on DB-only relational/ACID storage as the canonical persistence model. Redis isn't relational and doesn't provide the ACID guarantees the wallet's invariants depend on.

See #475 and #613 for the broader rationale.