Note deferred cookies-jar work for the YouTube bot gate in the backlog

BACKLOG.md

@@ -36,6 +36,16 @@ bottom as they come up.
 - [x] Per-song notes (key / capo / arrangement cues) on playlist entries.
 
 ## Robustness
+- [ ] **Cookies jar for the YouTube bot gate (deferred 2026-08-27 — not being tackled yet).**
+      `runYtdlpResilient()` already recovers from "Sign in to confirm you're not a bot"
+      by retrying against `YTDLP_FALLBACK_CLIENTS`, so saves no longer fail. The residual
+      cost: while the gate is active, `tv_simply`/`android_vr`/`mweb` typically expose only
+      progressive itag 18, so those saves land at **360p instead of 720p** (`web_embedded`
+      keeps the full adaptive ladder when it works). Fix would be to supply a Netscape
+      cookies jar so the default client stays available: the server already honours
+      `YTDLP_COOKIES=<path>` when the file exists — what's missing is mounting the jar into
+      the container (compose volume + env) and a refresh story for when the cookies expire.
+      Only worth doing if 360p saves become noticeable in practice.
 - [x] Sanitize `video_id` in `cache_download` (reject path separators).
 - [x] Gate the embedded yt-dlp behind a build flag so debug builds compile faster.
 - [x] Surface yt-dlp extraction failures with a retry button.