Adding Streamdal and Workflow Engines

[Dosplatos]

Checklist:

• [x] I've read and understood Contributing Guidelines.
• [x] I've added the new resource at the end of its section.
• [x] This resource is out there for a while, and actively maintained.
• [x] This resource is popular enough and has at least a few hundred stars on GitHub.

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Streamdal gives a highly performant way to handle any kind of validation, data transformation, or other workflow you need to happen fast (the Wasm makes it really fast). It's embedded into application code and executes the workflows at runtime, on the client side. So no network hops.

Very well documented, and the Node SDK comes with a great sandbox to help understand how the engine is used. Should be a fantastic addition to this awesome list!