fix: theme persistence

save user theme preferences  in session instead of localStorage

app/constants/session.ts

@@ -0,0 +1 @@
+export const PREFER_DARK_THEME = 'prefer_dark_theme';

app/controllers/apps_controller.ts

@@ -1,7 +1,17 @@
+import { PREFER_DARK_THEME } from '#constants/session';
+import { updateUserThemeValidator } from '#validators/user_theme';
 import type { HttpContext } from '@adonisjs/core/http';
 
 export default class AppsController {
   index({ inertia }: HttpContext) {
     return inertia.render('home');
   }
+
+  async updateUserTheme({ request, session, response }: HttpContext) {
+    const { preferDarkTheme } = await request.validateUsing(
+      updateUserThemeValidator
+    );
+    session.put(PREFER_DARK_THEME, preferDarkTheme);
+    return response.ok('ok');
+  }
 }

app/validators/user_theme.ts

@@ -0,0 +1,7 @@
+import vine from '@vinejs/vine';
+
+export const updateUserThemeValidator = vine.compile(
+  vine.object({
+    preferDarkTheme: vine.boolean(),
+  })
+);