completions: merge different aliases of same flag

Basics

• I have done a basic search through the issue tracker to find similar or related issues.
• I have made myself familiar with the available features of Nushell for the particular area this enhancement request touches.

Related problem

very often, a flag has a long and short aliases. for example, -v and --version. or different aliases like --at-operation, --at-op in jj.

1. right now they appear as separate entries, often far apart from each other (because -- and - flags cluster together) which adds a lot of clutter and makes it much harder to navigate completions for programs you're unfamiliar with.
2. if you know the short name and want to know the long name (or vice-versa), the current workflow appears to be just manually scanning for the same description, which isn't ideal.

Describe the solution you'd like

merge multiple versions to a single completion entry, by listing all of them together for the common case of single long + single short, we can use the existing --long_flag (-l) convention from defs.

for multiple long and/or multiple short, I guess we can comma separate them.

even better if it intelligently groups together flags that have the same description, or where the description of the short version is the name of the long version

maybe some or all of this should be optional.

Describe alternatives you've considered

No response

Additional context and details

No response