Add playlist link button to watchlist pages; fix LastCinema slug

- Each panel now has a full-width '→ OPEN FULL PLAYLIST ON YOUTUBE' link
  below the embed — resolves YouTube showing single video instead of playlist
- Link inherits panel accent color, inverts on hover
- Renamed TheLastCinema-watchlist.md → LastCinema-watchlist.md so build.py
  generates lastcinema.html (matching hub link)
- Regenerated all 5 collection pages

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Watchlists/LastCinema-watchlist.md

@@ -0,0 +1,27 @@
+# The Last Cinema
+
+---
+
+>>on-first-load - lightbox - "Short films are the ones that got away. The feature film has a machine behind it — financing, distribution, marketing. The short film has a person behind it, usually broke, always obsessed. This collection is experimental work, avant-garde work, cult films, archive footage — cinema that exists outside the machine. Watch them when you have 10 minutes and a reason to feel something strange."
+
+---
+
+- **Experimental, Avant-Garde & Surreal Short Films \- YouTube**
+  - URL: https://www.youtube.com/playlist?list=PLx8zUw4PoWHgqy5bD0HcuuTgVqPOSNrHn
+
+- **Films: Cult Movies \- YouTube**
+  - URL: https://www.youtube.com/playlist?list=PLqqTsphh57d5czFm-bK404ripWFI-2a8c
+
+- **A History of Unique Visual Art \(Mega Compilation\) \- YouTube**
+  - URL: https://www.youtube.com/playlist?list=PLHPWDhsjb4ZFGV_3ezZHcQ142HwppW--Y
+
+- **Loops \- YouTube**
+  - URL: https://www.youtube.com/playlist?list=PLSpz5qTrO-GnziQviNzmarSRpTbe8OcgQ
+
+- **Movies \(Homerecorded Delicatessens\) \- YouTube**
+  - URL: https://www.youtube.com/playlist?list=PLo16qa3p5doyYLVw4JCm7bGBH7nf4vLnV
+
+- **Archives \- YouTube**
+  - URL: https://www.youtube.com/playlist?list=PLjf4Mu2Zp3kYtBZB38-huwZA3DJaIcGN_
+
+---