feat: improve markdown and bold font rendering

modules/capabilities/terminal.nix

@@ -29,6 +29,8 @@ in
           size = 11;
         };
         settings = {
+          bold_font = "postscript_name=JetBrainsMono-Bold";
+          bold_italic_font = "postscript_name=JetBrainsMono-BoldItalic";
           disable_ligatures = "always";
           scrollback_lines = 10000;
           enable_audio_bell = false;