feat: 截图线程 + 编码线程。

每个显示器分别使用一个截图线程和一个编码（png+base64）线程。避免程序不明原因崩溃。

src/components/screen-view.tsx

@@ -0,0 +1,38 @@
+import { invoke } from '@tauri-apps/api';
+import { listen } from '@tauri-apps/api/event';
+import { Component, createEffect, createSignal, onCleanup } from 'solid-js';
+
+type ScreenViewProps = {
+  displayId: number;
+};
+
+async function subscribeScreenshotUpdate(displayId: number) {
+  await invoke('subscribe_encoded_screenshot_updated', {
+    displayId,
+  });
+}
+
+export const ScreenView: Component<ScreenViewProps> = (props) => {
+  const [image, setImage] = createSignal<string>();
+  createEffect(() => {
+    const unlisten = listen<{ base64_image: string; display_id: number }>(
+      'encoded-screenshot-updated',
+      (event) => {
+        if (event.payload.display_id === props.displayId) {
+          setImage(event.payload.base64_image);
+        }
+
+        console.log(event.payload.display_id, props.displayId);
+      },
+    );
+    subscribeScreenshotUpdate(props.displayId);
+
+    onCleanup(() => {
+      unlisten.then((unlisten) => {
+        unlisten();
+      });
+    });
+  });
+
+  return <img src={image()} class="object-contain" />;
+};