feat: add Umami Analytics integration and widget (#5362)

Co-authored-by: Josh G <febrile42@users.noreply.github.com>
Co-authored-by: Meier Lukas <meierschlumpf@gmail.com>
Co-authored-by: Thomas <thomas@ajnart.fr>

.gitignore

@@ -71,4 +71,4 @@ en.d.json.ts
 
 # personal agent config
 AGENTS.md
-.opencode
+.opencode