refactor: rename app id to io.fortressia.Echidna

Won't hurt, noone used this app yet.

src/main.rs

@@ -9,7 +9,7 @@ use components::app;
 use gtk::prelude::ApplicationExtManual;
 
 fn main() {
-    let app = EchidnaEditor::new("land.echidna.editor");
+    let app = EchidnaEditor::new("io.fortressia.Echidna");
 
     std::process::exit(app.run());
 }