1. add on_connect & on_close directives to conf/full.conf;
2. let http_hooks env overwrite support multi values; e.g.
SRS_VHOST_HTTP_HOOKS_ON_CONNECT="http://127.0.0.1/api/connecthttp://localhost/api/connect"
related to
https://github.com/ossrs/srs/issues/1222#issuecomment-2170424703
Above comments said `http_hook` env may not works as expected, as I
found there are still has some issue in `http_hooks` env configuration,
but this PR may not target above problem.
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Co-authored-by: winlin <winlinvip@gmail.com>