Add CloudingHost startup offer

[robotliza2024-stack]

What changed

Added the CloudingHost vendor record with its Startup Program and one offer covering up to $5,000 in first-year cloud credits, priority support and mentorship, and the permanent 20% post-program discount.

Resolves #608

Sources

• https://www.cloudinghost.com/en/startup-program/

Certification

• I changed only allowed repository content and did not mix vendor YAML with other paths.
• 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.
• My commits include a Signed-off-by line.