Feature: Implement metadata functionality (#12049)

### What problem does this PR solve?

Feature: Implement metadata functionality

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

web/src/pages/dataset/dataset-setting/form-schema.ts

@@ -83,6 +83,18 @@ export const formSchema = z
               path: ['entity_types'],
             },
           ),
+        metadata: z
+          .array(
+            z
+              .object({
+                key: z.string().optional(),
+                description: z.string().optional(),
+                enum: z.array(z.string().optional()).optional(),
+              })
+              .optional(),
+          )
+          .optional(),
+        enable_metadata: z.boolean().optional(),
       })
       .optional(),
     pagerank: z.number(),