fix(windows): hide engine consoles

Disable the native Windows frame at startup and render in-app window controls so packaged builds use Firelink's own titlebar placement instead of the default OS chrome.

Apply CREATE_NO_WINDOW to raw child processes used by the aria2 daemon and shared engine version checks. Route ffmpeg and deno checks through the same hidden version-check helper so Settings > Engine does not flash console windows.

Normalize Windows extended-length paths before returning approved download roots to the UI, while keeping canonicalization for backend safety checks. Detect yt-dlp's embedded runtime per platform so Windows onedir builds look for python*.dll instead of macOS Python.framework.

Verification: npm run build; cargo check --manifest-path src-tauri/Cargo.toml; cargo test --manifest-path src-tauri/Cargo.toml --lib; node --check scripts/smoke-packaged-app.js; Ruby YAML parse for .github/workflows/release.yml; git diff --check.

src/App.tsx

@@ -16,6 +16,7 @@ import SchedulerView from "./components/SchedulerView";
 import SpeedLimiterView from "./components/SpeedLimiterView";
 import LogsView from "./components/LogsView";
 import { KeychainPermissionModal } from "./components/KeychainPermissionModal";
+import { WindowControls } from "./components/WindowControls";
 import { useToast } from "./contexts/ToastContext";
 import { openUrl } from '@tauri-apps/plugin-opener';
 import { usePlatformInfo } from './utils/platform';
@@ -576,6 +577,7 @@ function App() {
 
   return (
     <div className="app-shell flex h-screen w-screen overflow-hidden text-text-primary">
+      {platform.os === 'windows' && <WindowControls />}
       <div
         className={`app-sidebar-shell relative z-20 shrink-0 transition-all duration-300 ease-[cubic-bezier(0.2,0.8,0.2,1)] ${
           isSidebarVisible ? 'opacity-100' : 'opacity-0 pointer-events-none'