feat: shared loading state + cleanup loading state management (#5835)

* feat: implement shared loading bar component and polished loading states across the app

* feat: align loading states + ensureQueryData changes

* fix: lint + bugs

* fix: skeleton for manage servers page

* fix: merge conflict fix

apps/app-frontend/src/store/loading.js

@@ -1,19 +0,0 @@
-import { defineStore } from 'pinia'
-
-export const useLoading = defineStore('loadingStore', {
-	state: () => ({
-		loading: false,
-		barEnabled: false,
-	}),
-	actions: {
-		setEnabled(enabled) {
-			this.barEnabled = enabled
-		},
-		startLoading() {
-			this.loading = true
-		},
-		stopLoading() {
-			this.loading = false
-		},
-	},
-})

apps/app-frontend/src/store/state.js

@@ -1,5 +1,4 @@
 import { useBreadcrumbs } from './breadcrumbs'
-import { useLoading } from './loading'
 import { useTheming } from './theme.ts'
 
-export { useBreadcrumbs, useLoading, useTheming }
+export { useBreadcrumbs, useTheming }