Add MAZ Assist startup program

[joaorgb15]

What changed

Adds MAZ Assist and its startup-specific offer providing approved startups one AI Employee Starter plan free for three months plus access to 1,000 targeted international decision-maker contacts.

Closes #1224

Sources

• https://www.mazassist.com/for-startups

Certification

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• Public sources substantiate every submitted factual value; any Sourcey-written prose is a neutral summary, not a fabricated vendor quote.
• I did not author verification, provenance, freshness, or signature claims.
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