feat: case-insensitive matching for --ignore-glob

[Germano0]

Currently, --ignore-glob performs case-sensitive matching. While this is consistent with standard glob behavior, it can be limiting in practice when working with directories or files that may have inconsistent casing.
For example, having

foo/
├── bar/
├── Bar/
├── BAR/
└── baz/

and running eza --tree foo --ignore-glob='bar', will only exclude "bar", but not "Bar" or "BAR".
A useful option in eza would be a case insensitive variant of --ignore-glob, called for example --ignore-glob-ci