docs: link canonical page and resolve audit advisories

[mustafazeydani]

What changed

• adds a prominent README link to the canonical OpenSyria public dataset page
• updates the shared fast-uri and js-yaml transitive overrides to patched releases

Why

The canonical link improves repository-to-site discovery. Newly published advisories made the enforced repository audit fail on the default branch, so the minimal patched transitive versions are included to restore a clean release gate.

Validation

• pnpm validate
• pnpm audit: zero known vulnerabilities
• git diff --check

No dataset records, schemas, release artifacts, or API pins changed, so no dataset version tag is required.