config: add Catppuccin theme and tweak editor settings

- Add high-contrast Catppuccin theme for OpenCode
- Enable Copilot edit prediction in Zed
- Increase Kitty font size and improve text rendering
- Fix trailing comma in OpenCode plugins config

home/.managed/zed/settings.linux.json

@@ -7,6 +7,9 @@
 // custom settings, run `zed: open default settings` from the
 // command palette (cmd-shift-p / ctrl-shift-p)
 {
+  "features": {
+    "edit_prediction_provider": "copilot"
+  },
   "vim_mode": false,
   "icon_theme": "Material Icon Theme",
   "use_system_path_prompts": false,