feat(server): add cloud indexer with Elasticsearch and Manticoresearch providers (#11835)

close CLOUD-137

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

- **New Features**
  - Introduced advanced workspace-scoped search and aggregation capabilities with support for complex queries, highlights, and pagination.
  - Added pluggable search providers: Elasticsearch and Manticoresearch.
  - New GraphQL queries, schema types, and resolver support for search and aggregation.
  - Enhanced configuration options for search providers in self-hosted and cloud deployments.
  - Added Docker Compose services and environment variables for Elasticsearch and Manticoresearch.
  - Integrated indexer service into deployment and CI workflows.

- **Bug Fixes**
  - Improved error handling with new user-friendly error messages for search provider and indexer issues.

- **Documentation**
  - Updated configuration examples and environment variable references for indexer and search providers.

- **Tests**
  - Added extensive end-to-end and provider-specific tests covering indexing, searching, aggregation, deletion, and error cases.
  - Included snapshot tests and test fixtures for search providers.

- **Chores**
  - Updated deployment scripts, Helm charts, and Kubernetes manifests to include indexer-related environment variables and secrets.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/admin/src/config.json

@@ -260,6 +260,33 @@
       "desc": "Customer.io token"
     }
   },
+  "indexer": {
+    "enabled": {
+      "type": "Boolean",
+      "desc": "Enable indexer plugin"
+    },
+    "provider.type": {
+      "type": "String",
+      "desc": "Indexer search service provider name",
+      "env": "AFFINE_INDEXER_SEARCH_PROVIDER"
+    },
+    "provider.endpoint": {
+      "type": "String",
+      "desc": "Indexer search service endpoint",
+      "env": "AFFINE_INDEXER_SEARCH_ENDPOINT"
+    },
+    "provider.username": {
+      "type": "String",
+      "desc": "Indexer search service auth username, if not set, basic auth will be disabled. Optional for elasticsearch",
+      "link": "https://www.elastic.co/guide/en/elasticsearch/reference/current/http-clients.html",
+      "env": "AFFINE_INDEXER_SEARCH_USERNAME"
+    },
+    "provider.password": {
+      "type": "String",
+      "desc": "Indexer search service auth password, if not set, basic auth will be disabled. Optional for elasticsearch",
+      "env": "AFFINE_INDEXER_SEARCH_PASSWORD"
+    }
+  },
   "oauth": {
     "providers.google": {
       "type": "Object",