fix(settings): improve error handling and success notifications in EvoBGP settings

Enhanced the error handling in the settings page by introducing a dedicated error message function. Added success and error toast notifications for better user feedback during settings save operations. Updated API key normalization to ensure consistent handling across the application.

app/(main)/settings/page.tsx

@@ -875,8 +875,11 @@ export default function SettingsPage() {
         await evo.saveSettings(patch)
         setEvoKeyDraft("")
         markSaved()
+        toast.success("Настройки EvoBGP сохранены")
       } catch (e) {
-        setEvoSaveErr(e instanceof Error ? e.message : "Ошибка сохранения")
+        const msg = e instanceof Error ? e.message : "Ошибка сохранения"
+        setEvoSaveErr(msg)
+        toast.error(msg)
       } finally {
         setEvoSaveBusy(false)
       }