REPL: fix hinting without expanding user

[IanButterworth]

Fixes #53884

Hints will show without expanding ~, then a tab will complete the shown hint, then a second tab on the resulting valid path expands ~. I think it makes sense?

Screen.Recording.2024-04-29.at.9.54.40.PM.mov

[tecosaur]

This looks like a nice change to me 😃

[IanButterworth]

This is going to require adding the hint kw to Pkg's complete_line. It makes me wonder whether there's a nonbreaking way to inform the system that we're generating a hint (so that different behavior might be given)

JuliaLang/Pkg.jl#3886

[IanButterworth]

I found a little weird behavior but it exists before this PR.

GitHub is the only path completion available, yet it doesn't show as a hint until there are 2 chars.

That can be for another PR