fix(Notion Node): Store lastTimeChecked as ISO string instead of moment object

[okxint]

Summary

The NotionTrigger node's poll() method stores a raw moment.js object into webhookData.lastTimeChecked:

webhookData.lastTimeChecked = moment().set({ second: 0, millisecond: 0 });

webhookData is backed by the workflow's staticData, which TypeORM serializes on every mutation. During serialization, TypeORM calls native Date.prototype methods on the stored value. Since a moment.js object is not a native Date instance, this throws:

TypeError: this is not a Date object.

This error propagates up through runPoll() → executeTrigger(true) → ActiveWorkflows.add(), where it gets wrapped as a WorkflowActivationError — preventing any workflow with a Notion Trigger from activating.

The fix appends .toISOString() so that a plain string is stored instead. The read-back path already wraps the value with moment(), which parses ISO strings without issue, so no changes are needed there.

Related Linear tickets, Github issues, and Community forum posts

Fixes #28445
https://linear.app/n8n/issue/GHC-7725

Review / Merge checklist

• I have seen this code, I have run this code, and I take responsibility for this code.
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• Docs updated or follow-up ticket created.
• Tests included.
• PR Labeled with Backport to Beta, Backport to Stable, or Backport to v1 (if the PR is an urgent fix that needs to be backported)

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