Expand the system package with some required features

[Peefy]

Discussed in https://github.com/orgs/kcl-lang/discussions/1887

^{Originally posted by tridentsx March 12, 2025}
I am trying to create a JSON Schema converter and there are some limitations that I think could be addressed in the system packagees

For example in the In net package support
is_IPv6() to validate ipv6 only which returns False for an ipv4 address

In datetime have functions to validate RFC 3339 dates and times and durations and also another for ISO 8601, having single pattern validation doesnt work for JSON schema. Where timezone is optional and where microseconds are optional.

For example all of these are valid accoring to JSON schema, for now I use regex to valiate but with regex I can't validate leap years Feb 29 etc ...
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