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/pkg/enums/knowledge_test.go

@@ -0,0 +1,12 @@
+package enums
+
+import "testing"
+
+func TestVectorDBTypeLabelIncludesLanceDB(t *testing.T) {
+	if VectorDBTypeLanceDB != "lancedb" {
+		t.Fatalf("VectorDBTypeLanceDB = %q, want %q", VectorDBTypeLanceDB, "lancedb")
+	}
+	if got := GetVectorDBTypeLabel(VectorDBTypeLanceDB); got != "LanceDB" {
+		t.Fatalf("GetVectorDBTypeLabel(VectorDBTypeLanceDB) = %q, want %q", got, "LanceDB")
+	}
+}