remove ivanm-dfinity-razer and uber-loaner host references

Both hosts are long dead. Removes their CSS files, taffybar host
config entries, and synergy aliases.

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

dotfiles/synergy.conf

@@ -15,11 +15,8 @@ section: aliases
     imalison-desktop
 	imalison-home 	justin-bieber-creek
   controlling:
-	uber-loaner
     imalison-mpb-arch
-    imalison-uber-loaner
     Livien-MacbookAir
-    kat-uber-loaner
     Dean-PC
     imalison-mbp
 	strixi-minaj