[NEOS-1683] New Transformer Form Clone is broken

[nickzelei]

The clone does not set the Source anymore which causes the full form to not surface.

It only sets the "config"

Should be as simple as doing form.setValue("source", base.source)

I think source still needs to be there in this flow.

File: frontend/apps/web/app/(mgmt)/[account]/new/transformer/page.tsx roughly line 171.

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