feat: no-select generic prompts in codeblocks

Makes it easier to copy console commands by e.g. triple-click

Signed-off-by: David Karlsson <35727626+dvdksn@users.noreply.github.com>

assets/css/code.css

@@ -378,6 +378,7 @@
     }
     /* GenericPrompt */
     .gp {
+      user-select: none;
       color: #8f5902;
     }
     /* GenericStrong */