Support for RegEx

[febinjoy]

Describe the enhancement you'd like
I would like to add support for regular expressions (RegEx) in Search-Tail to allow more complex and flexible search patterns.

Why is this enhancement important?
RegEx support will enable users to search for specific patterns in logs that simple keyword searches cannot capture. This provides powerful search capabilities, making it easier to identify complex log entries and patterns.

Describe alternatives you've considered
Alternatives considered include using basic keyword searches or external tools with RegEx capabilities, but integrating this directly into Search-Tail will provide a seamless and powerful user experience.

Additional context
This feature could include options for case-insensitive searches, multiple RegEx patterns, and more.