feat(execution): Add node content override capability

Add ability to override node content dynamically during execution

- Add OverrideData interface for specifying node content changes
- Implement content override logic in executeStep
- Add GitHub webhook support for issue and comment data injection
- Support overriding both text and textGeneration node types

This enables dynamic content injection into workflow nodes, particularly
useful for webhook-triggered executions where external data needs to be
incorporated into the flow.

BREAKING CHANGE: executeStep now accepts overrideData parameter that can
modify node content during execution

app/(playground)/p/[agentId]/lib/execution.ts

@@ -411,13 +411,18 @@ async function performFlowExecution(
 	}
 }
 
-interface ExecuteStepOptions {
+interface OverrideData {
+	nodeId: NodeId;
+	data: string;
+}
+interface ExecuteStepParams {
 	agentId: AgentId;
 	flowId: FlowId;
 	executionId: ExecutionId;
 	stepId: StepId;
 	artifacts: Artifact[];
 	stream?: boolean;
+	overrideData?: OverrideData[];
 }
 export async function executeStep({
 	agentId,
@@ -426,7 +431,8 @@ export async function executeStep({
 	stepId,
 	artifacts,
 	stream,
-}: ExecuteStepOptions) {
+	overrideData,
+}: ExecuteStepParams) {
 	const agent = await db.query.agents.findFirst({
 		where: (agents, { eq }) => eq(agents.id, agentId),
 	});
@@ -455,11 +461,43 @@ export async function executeStep({
 	if (node === undefined) {
 		throw new Error("Node not found");
 	}
+	let executionNode = node;
+	const overrideDataMap = new Map(
+		overrideData?.map(({ nodeId, data }) => [nodeId, data]) ?? [],
+	);
+	if (overrideDataMap.has(executionNode.id)) {
+		switch (executionNode.content.type) {
+			case "textGeneration":
+				executionNode = {
+					...executionNode,
+					content: {
+						...executionNode.content,
+						instruction:
+							overrideDataMap.get(executionNode.id) ??
+							executionNode.content.instruction,
+					},
+				} as Node;
+				break;
+			case "text":
+				executionNode = {
+					...executeNode,
+					content: {
+						...executionNode.content,
+						text:
+							overrideDataMap.get(executionNode.id) ??
+							executionNode.content.text,
+					},
+				} as Node;
+				break;
+			default:
+				break;
+		}
+	}
 
 	const context: ExecutionContext = {
 		agentId,
 		executionId,
-		node,
+		node: executionNode,
 		artifacts,
 		nodes: graph.nodes,
 		connections: graph.connections,

app/webhooks/github/route.ts

@@ -30,9 +30,10 @@ export async function POST(request: NextRequest) {
 
 	const id = request.headers.get("X-GitHub-Delivery") ?? "";
 	const name = request.headers.get("X-GitHub-Event") as WebhookEventName;
-	const payload = JSON.parse(body);
-	const event = { id, name, payload };
+	const rawPayload = JSON.parse(body);
+	const event = { id, name, payload: rawPayload };
 	assertIssueCommentEvent(event);
+	const payload = event.payload;
 
 	const command = parseCommand(payload.comment.body);
 	if (command === null) {
@@ -91,6 +92,24 @@ export async function POST(request: NextRequest) {
 					runStartedAt: flowRunStartedAt,
 				};
 
+				const overrideData = integrationSetting.eventNodeMappings
+					.map((eventNodeMapping) => {
+						switch (eventNodeMapping.event) {
+							case "comment.body":
+								return {
+									nodeId: eventNodeMapping.nodeId,
+									data: command.content,
+								};
+							case "issue.title":
+								return {
+									nodeId: eventNodeMapping.nodeId,
+									data: payload.issue.title,
+								};
+							default:
+								return null;
+						}
+					})
+					.filter((overrideData) => overrideData !== null);
 				const finalExecution = await performFlowExecution({
 					initialExecution,
 					executeStepFn: (stepId) =>
@@ -100,6 +119,7 @@ export async function POST(request: NextRequest) {
 							executionId: executionId,
 							stepId: stepId,
 							artifacts: initialExecution.artifacts,
+							overrideData,
 						}),
 					onExecutionChange: (execution) => {
 						initialExecution = execution;