feat(localization): expand language support and enhance UI for user settings

- Added support for additional UI locales including Cebuano and Spanish, improving accessibility for a broader user base.
- Updated language selection components in the AppHeader and SettingsWidget to reflect new language options, enhancing user experience.
- Enhanced localization of various UI elements across components, ensuring consistent language representation and improved user engagement.
- Implemented logic to synchronize user language preferences with backend settings, providing a seamless experience when changing languages.

frontend/src/components/falukant/SaleSection.vue

@@ -10,7 +10,7 @@
               <th>{{ $t('falukant.branch.sale.quality') }}</th>
               <th>{{ $t('falukant.branch.sale.quantity') }}</th>
               <th>{{ $t('falukant.branch.sale.sell') }}</th>
-              <th>Bessere Preise</th>
+              <th>{{ $t('falukant.branch.revenue.betterPrices') }}</th>
             </tr>
           </thead>
           <tbody>

frontend/src/components/falukant/StorageSection.vue

@@ -165,7 +165,7 @@
             });
           } catch (err) {
             console.error(err);
-            showError(this, 'Fehler beim Kaufen eines Teils der Lagerkapazität.');
+            showError(this, this.$t('falukant.branch.storage.buyPartialError'));
           }
           remainingAmount -= toBuy;
         }
@@ -186,7 +186,7 @@
         .then(() => this.loadStorageData())
         .catch(err => {
           console.error(err);
-          showError(this, 'Fehler beim Verkaufen der Lagerkapazität.');
+          showError(this, this.$t('falukant.branch.storage.sellError'));
         });
       },
       getCostOfType(labelTr) {