feat: add Brandfetch plugin

[bensabic]

Summary

Adds Brandfetch plugin with the following action:

• Get Brand: Retrieve brand assets by domain, stock ticker, or ISIN

Features:

• Identifier type selector (Domain, Ticker, ISIN) with format validation
• Returns name, description, logo URL, icon URL, colors, links, and industry
• Uses brandfetch.com for free connection testing

Test plan

• Connection test validates credentials
• Actions execute successfully in a workflow
• Format validation works for each identifier type
• Error handling works for invalid inputs

[vercel]

@bensabic is attempting to deploy a commit to the Vercel Labs Team on Vercel.

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