Turn home button into a 'go back to start of nav history'

src/state/models/navigation.ts

@@ -107,6 +107,12 @@ export class NavigationTabModel {
     }
   }
 
+  goBackToZero() {
+    if (this.canGoBack) {
+      this.index = 0
+    }
+  }
+
   goForward() {
     if (this.canGoForward) {
       this.index++

src/view/shell/mobile/index.tsx

@@ -134,7 +134,7 @@ export const MobileShell: React.FC = observer(() => {
     if (store.nav.tab.current.url === '/') {
       scrollElRef.current?.scrollToOffset({offset: 0})
     } else {
-      store.nav.navigate('/')
+      store.nav.tab.goBackToZero()
     }
   }
   const onPressMenu = () => setMainMenuActive(true)