feat: add get lectures

[ACaiCat]

添加获取已报名讲座的接口

[
    {
        "category": "“信息”系列讲座",
        "issue_number": 448,
        "title": "Web of Science助您高效开题、选题及科研创新",
        "speaker": " 王思茗（Web of Science数据库）",
        "timestamp": "1762887600000",
        "location": "腾讯会议直播",
        "attendance_status": "请按时参加讲座"
    },
    {
        "category": "“信息”系列讲座",
        "issue_number": 447,
        "title": "大数据视角下的实证研究——基于RESSET数据库",
        "speaker": "杨欣蕾 （RESSET数据库）",
        "timestamp": "1760468400000",
        "location": "腾讯会议直播",
        "attendance_status": "已听取"
    }
]

[Copilot]

Pull Request Overview

This PR adds functionality to retrieve lecture information from the academic system. It introduces a new Lecture model and a GetLectures method to fetch registered lecture data.

• Adds Lecture struct to represent lecture information with fields like category, issue number, title, speaker, time, location, and attendance status
• Implements GetLectures method to parse HTML and extract lecture data
• Adds corresponding test case and constant URL for the lecture endpoint

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
model.go	Defines the Lecture struct with JSON tags for lecture information
lecture.go	Implements GetLectures method to fetch and parse lecture data from HTML
jwch_test.go	Adds test case for the new GetLectures functionality
constants/constants.go	Adds LectureURL constant for the lecture endpoint

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[ozline]

@klxiaoniu 看看

[renbaoshuo]

我看完了已经

[klxiaoniu]

获取已报名讲座的用途是什么

[ACaiCat]

获取已报名讲座的用途是什么

想像考试一样塞进课表，或者日历的API里

[ozline]

晚上合入开跑

[ozline]

readme 里给的 demo timestamp 字段是不对的，应该是个 int64，看了一下具体实现里面那个数据类型是 int64，没什么问题