feat: refactor createDatabase method to remove databaseNodeId parameter and implement findOptimalNode in DatabaseNodeService for improved database node selection

src/databaseManager/databaseNode/database.node.service.ts

@@ -18,6 +18,22 @@ export class DatabaseNodeService extends DatabaseEncryptionService {
     return this.databaseNodeRepository.findOne({ where: { id } });
   }
 
+  async findOptimalNode(): Promise<DatabaseNode | null> {
+    const nodes = await this.databaseNodeRepository.find({
+      relations: ["databases"],
+    });
+
+    if (nodes.length === 0) {
+      return null;
+    }
+
+    return nodes.reduce((optimalNode, currentNode) => {
+      const currentCount = currentNode.databases?.length || 0;
+      const optimalCount = optimalNode.databases?.length || 0;
+      return currentCount < optimalCount ? currentNode : optimalNode;
+    });
+  }
+
   async initDatabase(
     data: {
       database: string;