mako: track config, add do-not-disturb mode for gamemode

Un-ignore mako/config and bring it under dotfiles so the gamemode
do-not-disturb mode syncs across machines. [mode=do-not-disturb]
invisible=1 suppresses popups while retaining notification history.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

mako/config

@@ -0,0 +1,8 @@
+background-color=#1d1f21
+text-color=#c5c8c6
+border-size=2
+border-color=#81a2be
+default-timeout=4000
+
+[mode=do-not-disturb]
+invisible=1