feat(profile): add username + preferred_locale; wire to Inertia + middleware

- DB: users.username (unique), users.preferred_locale (default from app.locale)
- Backend: validation, model fillable; share supportedLocales; SetLocaleFromUser
- Frontend: profile page fields + types
- Filament: SuperAdmin profile page with username/language

feat(admin-nav): move Tasks to Bibliothek and add menu labels

fix(tasks-table): show localized title/emotion/event type; add translated headers

feat(l10n): add missing table headers for emotions and event types; normalize en/de files

refactor: tidy translations for tasks/emotions/event types

app/Http/Requests/Settings/ProfileUpdateRequest.php

@@ -16,6 +16,20 @@ class ProfileUpdateRequest extends FormRequest
      */
     public function rules(): array
     {
+        $supportedLocales = collect(explode(',', (string) env('APP_SUPPORTED_LOCALES', 'de,en')))
+            ->map(fn ($l) => trim((string) $l))
+            ->filter()
+            ->unique()
+            ->values()
+            ->all();
+
+        if (empty($supportedLocales)) {
+            $supportedLocales = array_values(array_unique(array_filter([
+                config('app.locale'),
+                config('app.fallback_locale'),
+            ])));
+        }
+
         return [
             'name' => ['required', 'string', 'max:255'],
 
@@ -27,6 +41,19 @@ class ProfileUpdateRequest extends FormRequest
                 'max:255',
                 Rule::unique(User::class)->ignore($this->user()->id),
             ],
+
+            'username' => [
+                'nullable',
+                'string',
+                'max:32',
+                Rule::unique(User::class)->ignore($this->user()->id),
+            ],
+
+            'preferred_locale' => [
+                'required',
+                'string',
+                Rule::in($supportedLocales),
+            ],
         ];
     }
 }