实现set_arg和get_arg类方法

[eya46]

实现这样的效果

@test.handle()
async def test_handle(matcher: Matcher, cmd: Annotated[Message, CommandArg()]):
    test.set_arg("key_t", cmd)
    matcher.set_arg("key", cmd)
    for index, i in enumerate([
        matcher.get_arg("key", cmd),
        test.get_arg("key_t"),
        matcher.get_arg("key"),
        test.get_arg("none", cmd),
        matcher.get_arg("none", cmd),
        test.get_arg("none"),
        matcher.get_arg("none"),
    ]):
        print(index, i)
    logger.success(cmd)

[codecov]

Codecov Report

Merging #2217 (3ee9d86) into master (a2f2b81) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #2217      +/-   ##
==========================================
+ Coverage   89.80%   89.82%   +0.01%     
==========================================
  Files          46       46              
  Lines        3345     3350       +5     
==========================================
+ Hits         3004     3009       +5     
  Misses        341      341              

Flag	Coverage Δ
unittests	89.82% <100.00%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
nonebot/internal/matcher/matcher.py	97.11% <100.00%> (+0.06%)	⬆️

[github-actions]

🚀 Deployed on https://deploy-preview-2217--nonebot2.netlify.app

[yanyongyu]

这是在干啥？

[eya46]

让Matcher()的情况也能get到matcher

但不知道该在啥时候reset，就写个变量，让它在ensure_context里被覆盖...