home: vim: highlight over-extended commit subjects

This is a more accurate name to describe what the function is doing.

modules/home/tmux/default.nix

@@ -6,7 +6,7 @@ let
     (config.my.home.wm.windowManager != null)
   ];
 
-  mkTerminalFlags = opt: flag:
+  mkTerminalFeature = opt: flag:
     let
       mkFlag = term: ''set -as terminal-features ",${term}:${flag}"'';
       enabledTerminals = lib.filterAttrs (_: v: v.${opt}) cfg.terminalFeatures;
@@ -123,9 +123,9 @@ in
       }
 
       # Force OSC8 hyperlinks for each relevant $TERM
-      ${mkTerminalFlags "hyperlinks" "hyperlinks"}
+      ${mkTerminalFeature "hyperlinks" "hyperlinks"}
       # Force 24-bit color for each relevant $TERM
-      ${mkTerminalFlags "trueColor" "RGB"}
+      ${mkTerminalFeature "trueColor" "RGB"}
     '';
   };
 }

modules/home/vim/after/queries/gitcommit/highlights.scm

@@ -0,0 +1,6 @@
+; extends
+
+; Highlight over-extended subject lines (rely on wrapping for message body)
+((subject) @comment.error
+  (#vim-match? @comment.error ".\{50,}")
+  (#offset! @comment.error 0 50 0 0))