feat & refactor: 支持app端签名的请求，支持右键操作书架书籍，逻辑大幅重构，更改默认的设备逻辑为自动注册，支持载入某些书籍内置的CSS、支持跳转正文注释等等

src/settingsPanel.ts

@@ -0,0 +1,49 @@
+// 设置面板的挂载/卸载。
+// 面板是全局单例，从用户菜单里唤起。
+
+import { createApp, h, type App } from 'vue'
+import SettingsView from './views/SettingsView.vue'
+import settingscss from './assets/settings.css?raw'
+
+const CONTAINER_ID = 'fqa-settings-root'
+const STYLE_ID = 'fqa-settings-style'
+
+let app: App | null = null
+let container: HTMLElement | null = null
+
+function injectStyle() {
+    if (document.getElementById(STYLE_ID)) return
+    const style = document.createElement('style')
+    style.id = STYLE_ID
+    style.textContent = settingscss
+    document.head.appendChild(style)
+}
+
+export function closeSettings(): void {
+    app?.unmount()
+    app = null
+    container?.remove()
+    container = null
+}
+
+export function openSettings(): void {
+    if (app) return
+    injectStyle()
+
+    container = document.createElement('div')
+    container.id = CONTAINER_ID
+    document.body.appendChild(container)
+
+    app = createApp({
+        render: () => h(SettingsView, { onClose: closeSettings }),
+    })
+    app.config.errorHandler = (err, _instance, info) => {
+        console.error(`[fqa:settings] Vue error (${info}):`, err)
+    }
+    app.mount(container)
+}
+
+export function toggleSettings(): void {
+    if (app) closeSettings()
+    else openSettings()
+}