feat(extension): P2 视频页悬浮按钮 + 右键菜单 + cookie 直通；P3 侧边栏首版

- contentScripts: 仅在支持的视频平台（B 站 / YouTube / 抖音 / 快手）注入悬浮 BiliNote 按钮，点击通过 webext-bridge 发 'bilinote-start' 给 background
- background: 处理 bilinote-start 与右键菜单点击；调 /api/generate_note；写 chrome.storage；自动打开侧边栏。logic/storage 是 Vue 反应式版本，service worker 不能 import，因此把常量抽到 logic/constants.ts
- contextMenus: onInstalled 时注册"用 BiliNote 总结此视频"，限定 4 个支持平台域名
- 浏览器 Cookie 同步：options 页加按钮，按平台读 chrome.cookies.getAll，序列化为 'name=value; ...' 后 POST 给后端 /api/update_downloader_cookie。chrome.cookies + contextMenus 权限补到 manifest
- 侧边栏（P3 首版）：从 storage 读最近任务并轮询，复用 TaskProgress + MarkdownView。markmap 思维导图与 RAG 问答推到后续
- 修 P1 endpoint 拼错的 bug：/api/get_models_by_provider 实际是 /api/model_enable，404 来自这里

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

BillNote_extension/src/logic/api.ts

@@ -34,7 +34,14 @@ export async function getProviders(): Promise<Provider[]> {
 }
 
 export async function getModelsByProvider(providerId: string): Promise<Model[]> {
-  return request<Model[]>(`/api/get_models_by_provider/${providerId}`)
+  return request<Model[]>(`/api/model_enable/${providerId}`)
+}
+
+export async function setDownloaderCookie(platform: string, cookie: string): Promise<void> {
+  await request('/api/update_downloader_cookie', {
+    method: 'POST',
+    body: JSON.stringify({ platform, cookie }),
+  })
 }
 
 export async function generateNote(payload: GenerateRequest): Promise<{ task_id: string }> {

BillNote_extension/src/logic/constants.ts

@@ -0,0 +1,18 @@
+import type { Settings } from './types'
+
+export const DEFAULT_BACKEND_URL = 'http://localhost:8483'
+
+export const DEFAULT_SETTINGS: Settings = {
+  backendUrl: DEFAULT_BACKEND_URL,
+  providerId: '',
+  modelName: '',
+  quality: 'medium',
+  screenshot: false,
+  link: false,
+  style: '',
+}
+
+export const MAX_TASKS = 30
+
+export const SETTINGS_KEY = 'bilinote-settings'
+export const TASKS_KEY = 'bilinote-tasks'

BillNote_extension/src/logic/cookies.ts

@@ -0,0 +1,38 @@
+import { setDownloaderCookie } from './api'
+import type { Platform } from './types'
+
+// 后端期望的 cookie 字符串格式：name=value; name=value; ...
+// 见 backend/app/downloaders/bilibili_downloader.py 的 split("; ")
+const COOKIE_DOMAINS: Record<Exclude<Platform, 'local'>, string> = {
+  bilibili: '.bilibili.com',
+  youtube: '.youtube.com',
+  douyin: '.douyin.com',
+  kuaishou: '.kuaishou.com',
+}
+
+export const SUPPORTED_COOKIE_PLATFORMS: Array<Exclude<Platform, 'local'>> = [
+  'bilibili',
+  'douyin',
+  'kuaishou',
+  'youtube',
+]
+
+export async function readBrowserCookies(platform: Exclude<Platform, 'local'>): Promise<string> {
+  const domain = COOKIE_DOMAINS[platform]
+  const list = await browser.cookies.getAll({ domain })
+  return list.map(c => `${c.name}=${c.value}`).join('; ')
+}
+
+export async function syncCookieToBackend(platform: Exclude<Platform, 'local'>): Promise<{ ok: boolean, count: number, error?: string }> {
+  try {
+    const cookieStr = await readBrowserCookies(platform)
+    if (!cookieStr)
+      return { ok: false, count: 0, error: '当前浏览器没有该域名的 cookie，先在浏览器内登录目标站点' }
+    const count = cookieStr.split('; ').length
+    await setDownloaderCookie(platform, cookieStr)
+    return { ok: true, count }
+  }
+  catch (e) {
+    return { ok: false, count: 0, error: (e as Error).message }
+  }
+}

BillNote_extension/src/logic/storage.ts

@@ -1,33 +1,22 @@
 import { useWebExtensionStorage } from '~/composables/useWebExtensionStorage'
 import type { Settings, TaskRecord } from './types'
+import { DEFAULT_SETTINGS, MAX_TASKS, SETTINGS_KEY, TASKS_KEY } from './constants'
 
-export const DEFAULT_BACKEND_URL = 'http://localhost:8483'
+export { DEFAULT_BACKEND_URL, DEFAULT_SETTINGS, MAX_TASKS } from './constants'
 
-export const DEFAULT_SETTINGS: Settings = {
-  backendUrl: DEFAULT_BACKEND_URL,
-  providerId: '',
-  modelName: '',
-  quality: 'medium',
-  screenshot: false,
-  link: false,
-  style: '',
-}
-
-// 全局共享设置（popup / options / sidepanel / background 都读这一份）
+// 全局共享设置（popup / options / sidepanel 三个 Vue 上下文都读这一份）
+// 注意：background service worker 不要 import 这个文件，改用 chrome.storage 直读
 export const { data: settings, dataReady: settingsReady } = useWebExtensionStorage<Settings>(
-  'bilinote-settings',
+  SETTINGS_KEY,
   DEFAULT_SETTINGS,
   { mergeDefaults: true },
 )
 
-// 历史任务列表，最近的在前
 export const { data: tasks, dataReady: tasksReady } = useWebExtensionStorage<TaskRecord[]>(
-  'bilinote-tasks',
+  TASKS_KEY,
   [],
 )
 
-export const MAX_TASKS = 30
-
 export function upsertTask(record: TaskRecord) {
   const list = tasks.value ?? []
   const idx = list.findIndex(t => t.taskId === record.taskId)