The default `GITHUB_TOKEN` cannot read `security-advisories`; that endpoint requires the `repository_advisories` permission, which is not available to the GitHub Actions installation token.
Switched to a fine-grained PAT stored in `GHSA_READ_TOKEN`.
Tested locally: the same PAT returns the full triage list
Changes
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- Switch to custom token
- Add a discord alert for new advisories
- Switch to python
