Add Remotion file write advisory references

[cookesan]

Adds Remotion file write advisory references to GHSA-g6pc-6676-c23j.

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-g6pc-6676-c23j/GHSA-g6pc-6676-c23j.json), JSON parses, git diff --check passes, and the exact-head worktree is clean.
• Revalidated the added public references in the diff; all resolve through their source site or registry.

[cookesan]

Rechecked this reference-only PR while keeping the open Advisory Database queue current.

Adds the direct upstream merge commit for GHSA-g6pc-6676-c23j. The advisory already references NVD, the upstream PR, the fixed release, package source, and external analysis; this PR adds the merge commit that links those references together.

Current audit, July 8, 2026:

• GHSA-g6pc-6676-c23j is live and not withdrawn.
• CVE-2026-30121 resolves in NVD with Analyzed status.
• PR Fix wrong data in GHSA-c32m-27pj-4xcj.json #6378 merged to main as commit e3fcb3382057bb0bf1b0128a4f40c557ece7527a.
• Release v4.0.410 is published and not marked draft or prerelease.
• npm remotion 4.0.410 resolves with package tarball and integrity metadata.
• Local JSON validation and whitespace checks pass, and the diff only changes this advisory.

No advisory data fields are changed.