feat: schema graph via FK introspection

- GET .../db-connections/:id/foreign-keys — per-dialect
  information_schema/pragma query through dbx_execute_query,
  identifier-whitelisted, read-role gated
- Databases page: Graph tab renders tables as radial SVG nodes with
  FK edges; hover highlights adjacency, click inspects the table
- demo stubs for edges + wider demo table set

Authored By: TDvorak <[email protected]>

packages/api-client/src/generated/services/DatabasesService.ts

@@ -8,6 +8,7 @@ import type { DBConnectionListResponse } from '../models/DBConnectionListRespons
 import type { DBConnectionTestResult } from '../models/DBConnectionTestResult';
 import type { DBDatabaseListResponse } from '../models/DBDatabaseListResponse';
 import type { DBDescribeResponse } from '../models/DBDescribeResponse';
+import type { DBForeignKeysResponse } from '../models/DBForeignKeysResponse';
 import type { DBQueryRequest } from '../models/DBQueryRequest';
 import type { DBQueryResponse } from '../models/DBQueryResponse';
 import type { DBRedisRequest } from '../models/DBRedisRequest';
@@ -244,6 +245,38 @@ export class DatabasesService {
             },
         });
     }
+    /**
+     * @returns DBForeignKeysResponse Foreign key edges for the schema graph
+     * @throws ApiError
+     */
+    public static listDbForeignKeys({
+        projectId,
+        connectionId,
+        database,
+        schema,
+    }: {
+        projectId: string,
+        connectionId: string,
+        database?: string,
+        schema?: string,
+    }): CancelablePromise<DBForeignKeysResponse> {
+        return __request(OpenAPI, {
+            method: 'GET',
+            url: '/projects/{projectID}/db-connections/{connectionID}/foreign-keys',
+            path: {
+                'projectID': projectId,
+                'connectionID': connectionId,
+            },
+            query: {
+                'database': database,
+                'schema': schema,
+            },
+            errors: {
+                404: `Error response`,
+                502: `Error response`,
+            },
+        });
+    }
     /**
      * @returns DBQueryResponse Query result (at most 100 rows)
      * @throws ApiError