catalog: add Netcore startup program

[boundarycraftlab]

What changed

Adds one new vendor record for Netcore and one active offer for its B2C Startup Program. The record captures up to $30,000 in platform credits, mentorship and ecosystem support, eligibility, rolling access, and the no-cost consideration.

Sources

• https://netcorecloud.com/startup-program/

Validation

• Pinned Sourcey Catalog Verifier passed: status valid, 1 vendor, 1 program, 1 offer
• Diff is data-only: vendors/ne/netcore.yaml
• Fresh catalog, issue, and PR searches found no existing Netcore record

Closes #408

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.

[auscaster]

Thanks for this. sourcey/validation is green, but the private evidence pass for this head could not locate support for every submitted fact, so sourcey/admission cannot go green yet.

Uncovered on the vendor record: the vendor name, the vendor description, the canonical domains value, the vendor category and the links values. The cited page could not be read at all, so nothing could be located against.

The cited URL redirects to netcore.ai, and evidence capture only follows the host you cited, so nothing could be read. Cite the canonical URL the vendor actually serves (the address you land on after the redirect).

Fix it on this same branch: either cite a public page that states the fact (add the URL to sources and reference its source_id from the record that needs it), or change the record to what the cited pages do say. Push to the branch and the checks re-run automatically.