feat: centralize baseURL and app experience for cloud and self hosted

apps/dashboard/src/lib/utils/store/app.ts

@@ -1,4 +1,6 @@
-import { writable } from 'svelte/store';
+import { derived, writable } from 'svelte/store';
+import { PUBLIC_IS_SELFHOSTED } from '$env/static/public';
+import { currentOrgPath } from './org';
 
 export const globalStore = writable<{
   isDark: boolean;
@@ -11,3 +13,20 @@ export const globalStore = writable<{
   orgSiteName: '',
   isStudent: undefined
 });
+
+/**
+ * Single source of truth: is this a student experience?
+ * Cloud: orgSite is always student. Self-hosted: check role.
+ */
+export const isStudentExperience = derived(globalStore, ($gs) => {
+  const isCloud = PUBLIC_IS_SELFHOSTED !== 'true';
+  if (isCloud) return $gs.isOrgSite;
+  return $gs.isStudent ?? false;
+});
+
+/**
+ * The root path for navigation: '/lms' for students, '/org/{siteName}' for admin/teacher
+ */
+export const basePath = derived([isStudentExperience, currentOrgPath], ([$isStudent, $orgPath]) =>
+  $isStudent ? '/lms' : $orgPath
+);