refactor: static single-provider settings form (no Add/Delete, form visible immediately); defaultSettings seeds one provider

src/settings.ts

@@ -26,11 +26,12 @@ export const APINEX_BASE_URL = 'https://api.apinex.bond/v1'
 const SETTINGS_KEY = 'settings'
 
 export function defaultSettings (): Settings {
+  const p = createApinexProvider()
   return {
     version: 1,
     auth: { mode: 'local' },
-    providers: [],
-    activeProviderId: null
+    providers: [p],
+    activeProviderId: p.id
   }
 }