feat: add LanceDB vector database provider

- Implemented LanceDBProvider for managing vector collections, including methods for creating, deleting, and searching collections.
- Added support for LanceDB configuration in VectorDBConfig.
- Introduced stub for LanceDB provider when not built with the appropriate tag.
- Updated provider initialization to include LanceDB as a supported type.
- Created types and interfaces for vector operations, including Vector, SearchRequest, and SearchResult.
- Added tests for VectorDBConfig unmarshalling and for ensuring proper error handling when LanceDB is not built.
- Updated enums to include LanceDB type and labels.
- Modified frontend enums to reflect the addition of LanceDB.

internal/ai/rag/vectordb/provider.go

@@ -18,7 +18,9 @@ func Init(cfg *config.VectorDBConfig) error {
 	var err error
 	switch enums.VectorDBType(cfg.Type) {
 	case enums.VectorDBTypeQdrant:
-		defaultProvider, err = NewQdrantProvider(cfg)
+		defaultProvider, err = NewQdrantProvider(&cfg.Qdrant)
+	case enums.VectorDBTypeLanceDB:
+		defaultProvider, err = NewLanceDBProvider(&cfg.LanceDB)
 	default:
 		return fmt.Errorf("unsupported vectordb type: %s", cfg.Type)
 	}