chore(server): disable indexer on self-host by default (#12452)

enable indexer using `compose.indexer.yml` on self-host:

```bash
docker compose -f compose.yml -f compose.indexer.yml up
```

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit

- **Chores**
  - Updated the build process in the development container to include building the reader package.
  - Added and configured a Manticore Search indexer service in the development container.
  - Removed the indexer service and related environment variables from the self-hosted Docker Compose setup and environment example file.

- **Documentation**
  - Improved documentation formatting for better readability.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

.devcontainer/docker-compose.yml

@@ -10,6 +10,7 @@ services:
     environment:
       DATABASE_URL: postgresql://affine:affine@db:5432/affine
       REDIS_SERVER_HOST: redis
+      AFFINE_INDEXER_SEARCH_ENDPOINT: http://indexer:9308
 
   db:
     image: pgvector/pgvector:pg16
@@ -23,5 +24,19 @@ services:
   redis:
     image: redis
 
+  indexer:
+    image: manticoresearch/manticore:${MANTICORE_VERSION:-9.2.14}
+    ulimits:
+      nproc: 65535
+      nofile:
+        soft: 65535
+        hard: 65535
+      memlock:
+        soft: -1
+        hard: -1
+    volumes:
+      - manticoresearch_data:/var/lib/manticore
+
 volumes:
   postgres-data:
+  manticoresearch_data: