The E2E caught a real leak: a non-nsfw (even anonymous) account could download
an adult artifact. In PocketBase, file protection is a per-FIELD flag, not
derived from the collection view rule — the original migration left releases.file
unprotected, so its URL was public despite the gated read rules.
- Add protected:true to the file field (correct for fresh installs).
- 1786500001_releases_protect_file.js: alter the field on the already-deployed
instance (applied migrations don't re-run, so the fix needs its own migration).
- Doc: correct the gating explanation (protection is the field flag; the file
token grant then re-checks the view rule).
With this, a protected file needs a file token whose grant re-checks the view
rule, so a clean account is denied the adult artifact.
