feat(config): respect REDIS_DB env var for queue and transmit

Allow operators to select a Redis logical database index via the
REDIS_DB environment variable. Without this, the BullMQ queue and the
@adonisjs/transmit Redis transport both implicitly used db 0, causing
key collisions when sharing a Redis instance across multiple services
or environments.

REDIS_DB is added to the env schema as an optional number; both
config/queue.ts and config/transmit.ts fall back to db 0 when unset,
preserving existing behavior.

admin/.env.example

@@ -12,6 +12,9 @@ DB_PASSWORD=password
 DB_SSL=false
 REDIS_HOST=localhost
 REDIS_PORT=6379
+# Optional: Redis logical database index (0-15). Defaults to 0 if unset.
+# Set this when sharing a Redis instance across services to avoid key collisions.
+# REDIS_DB=0
 # Storage path for NOMAD content (ZIM files, maps, etc.)
 # On Windows dev, use an absolute path like: C:/nomad-storage
 # On Linux production, use: /opt/project-nomad/storage

admin/config/queue.ts

@@ -4,6 +4,7 @@ const queueConfig = {
   connection: {
     host: env.get('REDIS_HOST'),
     port: env.get('REDIS_PORT') ?? 6379,
+    db: env.get('REDIS_DB') ?? 0,
   },
 }
 

admin/config/transmit.ts

@@ -8,6 +8,7 @@ export default defineConfig({
     driver: redis({
       host: env.get('REDIS_HOST'),
       port: env.get('REDIS_PORT'),
+      db: env.get('REDIS_DB') ?? 0,
       keyPrefix: 'transmit:',
     })
   }

admin/start/env.ts

@@ -54,6 +54,7 @@ export default await Env.create(new URL('../', import.meta.url), {
   */
   REDIS_HOST: Env.schema.string({ format: 'host' }),
   REDIS_PORT: Env.schema.number(),
+  REDIS_DB: Env.schema.number.optional(),
 
   /*
   |----------------------------------------------------------