Explore possibility of webhooks that enable workflow automations

## Context

From a support ticket: https://cds-snc.freshdesk.com/a/tickets/28891

> Can we use webhooks from an external software like N8N in GCForms. I want to set up a webhook trigger when a form is submitted in N8N

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From meeting with another client:

- using javascript to funnel / redirect forms with different branching logic to different destinations, leveraging rules for triggering different workflows

No files, tests, or entry points are named. Start by reviewing the linked support ticket and the client workflow examples to determine the webhook and branching requirements; done should be a decided, scoped implementation plan or a documented conclusion about feasibility.

Written by the indexing model from the issue text.