feat: Create execution model

packages/backend/src/models/execution.ts

@@ -0,0 +1,33 @@
+import Base from './base';
+import Flow from './flow';
+
+class Execution extends Base {
+  id!: string;
+  flowId!: number;
+  testRun: boolean;
+
+  static tableName = 'executions';
+
+  static jsonSchema = {
+    type: 'object',
+
+    properties: {
+      id: { type: 'string' },
+      flowId: { type: 'integer' },
+      testRun: { type: 'boolean' },
+    },
+  };
+
+  static relationMappings = () => ({
+    flow: {
+      relation: Base.BelongsToOneRelation,
+      modelClass: Flow,
+      join: {
+        from: 'executions.flow_id',
+        to: 'flows.id',
+      },
+    },
+  });
+}
+
+export default Execution;