overzealous host and domain restrictions in 'Edit Host Override Alias'

[simonmcnair]

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Describe the bug
This is similar to #7492 which has been open for 5 months and relates to dns overrides rather than query forwarding. According to this https://www.rfc-editor.org/rfc/rfc2181#section-11 the only limitations on DNS names is the 'length of the label and the full name'. underscores anywhere in DNS are acceptable.

Tip: to validate your setup was working with the previous version, use opnsense-revert (https://docs.opnsense.org/manual/opnsense_tools.html#opnsense-revert)

To Reproduce

Steps to reproduce the behavior:

1. Go to -> ubound dns -> overrides
2. Click on '-> add alias
3. Scroll down to -> host
4. See error - > enter domain or host that includes an underscore.

Expected behavior
underscore should be accepted as hosts and domains within ubound

Describe alternatives you considered

A clear and concise description of any alternative solutions or workaround you considered.

Screenshots

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Relevant log files

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Additional context

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Environment

Software version used and hardware type if relevant, e.g.:

OPNsense 23.7.8 (amd64).
Intel® Xeon™ E3-1225V5 3.3Ghz Quad Core
Network Intel® I210-AT