feat: study modes (fast/parallel) and course-container completion fix

- settings: study.mode fast|normal and study.parallel 1-5

- normal mode: one headless browser per video, visibility keep-alive, auto-degrade when the platform enforces order

- report study/log/detail/save before isComplete; drop lastProgressTime on completion

- complete periodType 10/13 container nodes and recompute counters via PUT calFinalScore

- capture mode: POST /api/capture records all XHR/fetch including new tabs

- UI: study mode in settings, capture / stop-capture menu items

.dockerignore

@@ -0,0 +1,24 @@
+# 构建上下文里不需要的东西。
+# data/ 必须排除：里面是本地账号库和 settings.json（含 api_key），
+# 运行期由 volume 挂进来，不能打进镜像层。
+
+.git
+.gitignore
+__pycache__/
+**/__pycache__/
+*.py[cod]
+*.pyo
+.venv
+venv/
+env/
+.idea/
+.vscode/
+data/
+*.db
+*.db-wal
+*.db-shm
+*.log
+*.imported
+.env
+docker-compose.override.yml
+node_modules/