refactor: replace ioredis with Bun's built-in RedisClient

[zulfikar-ditya]

Summary

• Cache (src/libs/cache/cache.ts) and health checks (src/modules/home/routes.ts) now use Bun.RedisClient directly — no more ioredis import in our code.
• BullMQ queue/worker (src/bull/queue/send-email.queue.ts, src/bull/worker/send-email.worker.ts) receive a plain connection-options object so BullMQ constructs its own ioredis internally. Our codebase no longer imports ioredis.
• Removed ioredis from dependencies. Added @eslint/js and globals to devDependencies (referenced by eslint.config.mjs but missing from the manifest, breaking the pre-commit hook). Fixed pre-existing lint errors in the ClickHouse migrate script that the hook now surfaces.

Notes

• BullMQ still pulls in ioredis transitively (it's a hard dependency of BullMQ). The win is that our code no longer touches it.
• Cache.set / Cache.flush now go through RedisClient.send(...) since Bun's typed methods don't accept TTL.
• Cache.disconnect() became synchronous because Bun.RedisClient.close() is sync.

Test plan

• bun run typecheck passes
• bun run lint passes
• bun run build succeeds
• bun run dev boots and /health returns healthy for redis and redisQueue
• Trigger a flow that enqueues an email job; confirm worker processes it

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