Add Multer upload cleanup fix references

[cookesan]

Adds Multer upload cleanup fix references to GHSA-3p4h-7m6x-2hcm.

Audit refresh, July 8, 2026:

• Confirmed the live PR is open, ready for review, merge-clean, and the visible advisory check is green.
• Rechecked the merge-base diff: exactly one advisory JSON file changes (advisories/github-reviewed/2026/06/GHSA-3p4h-7m6x-2hcm/GHSA-3p4h-7m6x-2hcm.json), JSON parses, git diff --check passes, and the exact-head worktree is clean.
• Revalidated the added public references and package-version evidence in the diff; all resolve through their source site or registry.

[cookesan]

Revalidated July 8, 2026: this remains scoped to adding Multer fixed-version evidence for GHSA-3p4h-7m6x-2hcm. The npm registry versions, upstream release tags, and both fix commits resolve; affected ranges, severity, and advisory metadata fields remain unchanged. Local checks passed with a single advisory JSON file changed, JSON parsing, git diff --check HEAD^..HEAD, and a clean worktree.