add NewConn4 to let user delegate the conn to UDPSession to close

bump xorsimd to add linux/loong64 support (#270)

awesome

do not reserve in kcp core, reserve bytes in callback func

fix recycle

add a depicted ASCII graph for general flow of the session

add license to source codes

fix for issue: #259

remove unused param

Squashed commit of the following:

commit 8d14f07
Author: xtaci <[email protected]>
Date:   Thu Jan 4 22:50:33 2024 +0800

    upd deps

commit b451b38
Author: xtaci <[email protected]>
Date:   Thu Jan 4 22:48:12 2024 +0800

    fix test

commit 8ebaec8
Author: xtaci <[email protected]>
Date:   Thu Jan 4 22:45:10 2024 +0800

    remove unused param

commit 0e5741b
Author: fuli <[email protected]>
Date:   Thu Jan 4 16:21:42 2024 +0800

    use latest packet compare

commit 97999b9
Author: fuli <[email protected]>
Date:   Thu Jan 4 16:07:08 2024 +0800

    face race in test

commit 446bead
Author: fuli <[email protected]>
Date:   Thu Jan 4 16:04:42 2024 +0800

    upd

commit 570e9b0
Author: fuli <[email protected]>
Date:   Thu Jan 4 16:03:17 2024 +0800

    revert some file

commit c665db2
Author: fuli <[email protected]>
Date:   Thu Jan 4 15:59:16 2024 +0800

    Revert "Revert "1. simplify readloop_xxx files & tx_xxx files by merging""

    This reverts commit 717b79a.

commit 717b79a
Author: fuli <[email protected]>
Date:   Thu Jan 4 15:58:30 2024 +0800

    Revert "1. simplify readloop_xxx files & tx_xxx files by merging"

    This reverts commit 681bda6.

commit 681bda6
Author: fuli <[email protected]>
Date:   Thu Jan 4 15:54:29 2024 +0800

    1. simplify readloop_xxx files & tx_xxx files by merging
    2. fix the race in owned packet test

commit 7974357
Author: xtaci <[email protected]>
Date:   Thu Jan 4 00:04:06 2024 +0800

    use unix.Milli

commit 375407b
Author: xtaci <[email protected]>
Date:   Wed Jan 3 23:40:01 2024 +0800

    add passive fec

Bump gopkg.in/yaml.v3 from 3.0.0-20200313102051-9f266ea9e77c to 3.0.0 (…

…#249)

Bumps gopkg.in/yaml.v3 from 3.0.0-20200313102051-9f266ea9e77c to 3.0.0.

---
updated-dependencies:
- dependency-name: gopkg.in/yaml.v3
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>