vscode: Don't hardcode icon

This also allows people to use a vscode
icon that is shipped with their theme. (provided it is called code)

Fixes #83846

pkgs/applications/editors/vscode/generic.nix

@@ -25,7 +25,7 @@ in
       comment = "Code Editing. Redefined.";
       genericName = "Text Editor";
       exec = executableName;
-      icon = "@out@/share/pixmaps/code.png";
+      icon = "code";
       startupNotify = "true";
       categories = "Utility;TextEditor;Development;IDE;";
       mimeType = "text/plain;inode/directory;";
@@ -37,7 +37,7 @@ in
         [Desktop Action new-empty-window]
         Name=New Empty Window
         Exec=${executableName} --new-window %F
-        Icon=@out@/share/pixmaps/code.png
+        Icon=code
       '';
     };
 
@@ -47,7 +47,7 @@ in
       comment = "Code Editing. Redefined.";
       genericName = "Text Editor";
       exec = executableName + " --open-url %U";
-      icon = "@out@/share/pixmaps/code.png";
+      icon = "code";
       startupNotify = "true";
       categories = "Utility;TextEditor;Development;IDE;";
       mimeType = "x-scheme-handler/vscode;";
@@ -83,10 +83,8 @@ in
         ln -s $out/lib/vscode/bin/${executableName} $out/bin
 
         mkdir -p $out/share/applications
-        substitute $desktopItem/share/applications/${executableName}.desktop $out/share/applications/${executableName}.desktop \
-          --subst-var out
-        substitute $urlHandlerDesktopItem/share/applications/${executableName}-url-handler.desktop $out/share/applications/${executableName}-url-handler.desktop \
-          --subst-var out
+        ln -s $desktopItem/share/applications/${executableName}.desktop $out/share/applications/${executableName}.desktop
+        ln -s $urlHandlerDesktopItem/share/applications/${executableName}-url-handler.desktop $out/share/applications/${executableName}-url-handler.desktop
 
         mkdir -p $out/share/pixmaps
         cp $out/lib/vscode/resources/app/resources/linux/code.png $out/share/pixmaps/code.png