Wild IP App: Add hexadecimal IPv4 support

[swimlane-marty]

Summary

Add support for nip.io-style, eight-character hexadecimal IPv4 labels to the Wild IP App.

For example:

• c0a864d3.ip.example.com → 192.168.100.211
• C0A864D3.ip.example.com → 192.168.100.211
• service.c0a864d3.ip.example.com → 192.168.100.211

Root cause

Wild IP already recognizes compact 32-character hexadecimal IPv6 labels, but its IPv4 parsing path only collects four decimal octets separated by dots or dashes. A single eight-character IPv4 hexadecimal label therefore failed parsing and produced no synthesized A record.

Changes

• recognize an exact eight-character hexadecimal IPv4 label after the existing decimal parser
• decode it in network byte order into an IPv4 address
• retain existing dotted, dashed, prefixed, and IPv6 parsing behavior
• pass decoded addresses through the existing allowedNetworks check
• bump the Wild IP App version from 6.0 to 6.1
• document compact hexadecimal IPv4 examples

Validation

• built TechnitiumLibrary.Net and Apps/WildIpApp/WildIpApp.csproj in Release mode using .NET SDK 10.0.302
• build completed with 0 warnings and 0 errors
• packaged and installed the resulting app on Technitium DNS Server v15.4
• live-tested dotted IPv4, dashed IPv4, lowercase and uppercase hexadecimal IPv4, arbitrary prefixes, dashed IPv6, compact hexadecimal IPv6, and allowedNetworks enforcement
• independently reviewed and approved by @mohammed-asadd in the fork staging PR

[ShreyasZare]

Thanks for the PR. Will test it out soon.