fix: guard getPendingAttemptCompletionToolUseId against multi-tool_use messages

When the last assistant message contains attempt_completion alongside
other tool_use blocks (e.g. read_file + attempt_completion) and the
process crashes before any tool_result is saved, the method previously
returned the attempt_completion ID. This caused resumeTaskFromHistory
to bypass the rewind and treat the task as completed, while the other
tool_uses never executed.

Now returns undefined when other tool_use blocks are present alongside
attempt_completion, allowing the rewind path to handle the cleanup
correctly.

Addresses review feedback from @roomote.

src/core/task/Task.ts

@@ -2129,6 +2129,13 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 				block.type === "tool_use" && block.name === "attempt_completion",
 		)
 
+		// Only treat as pending completion if there are no other unanswered
+		// tool_use blocks — otherwise the rewind path is more appropriate.
+		if (toolUse) {
+			const hasOtherToolUse = content.some((block) => block.type === "tool_use" && block !== toolUse)
+			if (hasOtherToolUse) return undefined
+		}
+
 		return toolUse?.id
 	}
 

src/core/task/__tests__/rewind-integration.spec.ts

@@ -456,13 +456,15 @@ describe("rewind-integration", () => {
 		expect(parsedContent.status).toBe("completed")
 	})
 
-	it("attempt_completion alongside another tool_use in same assistant message", () => {
+	it("attempt_completion alongside another tool_use in same assistant message returns undefined", () => {
 		const task = createTask(mockProvider)
 		const now = Date.now()
 
 		// Edge case: assistant message contains both a read_file tool_use and
 		// an attempt_completion tool_use. getPendingAttemptCompletionToolUseId
-		// should still detect the attempt_completion.
+		// should return undefined so the rewind path is used instead —
+		// the other tool_uses never executed, so treating it as a pending
+		// completion would bypass the rewind and produce misleading context.
 		task.apiConversationHistory = [
 			{
 				role: "user",
@@ -491,6 +493,6 @@ describe("rewind-integration", () => {
 		] as any[]
 
 		const pendingId: string | undefined = (task as any).getPendingAttemptCompletionToolUseId()
-		expect(pendingId).toBe("toolu_completion_888")
+		expect(pendingId).toBeUndefined()
 	})
 })