PR: Use single row for file name and path and use gray for paths in file switcher

[juanis2112]

Description of Changes

• Wrote at least one-line docstrings (for any new functions)
• Added unit test(s) covering the changes (if testable)
• Included a screenshot (if affecting the UI)

Changed file switcher to use a single row for a file name and its path and changed paths color to gray.

Issue(s) Resolved

Part of #8580 (Items 1 and 3)

Affirmation

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and understand I am releasing the same under Spyder's MIT (Expat) license.

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Juanis2112

[CAM-Gerlach]

Looking good! Could you align the file paths to the right instead of the left of the dialog? That way they wouldn't be so squished against the file names and would look much cleaner overall. Thanks!

[dalthviz]

Thanks @juanis2112! I left some comments to not hardcode the color and other details :)

[dalthviz]

About @CAM-Gerlach comment, what do you think @ccordoba12 ? From what I see in VSCode the paths are align to the left. Although, they seem kind of squished in the preview @juanis2112 uploaded as @CAM-Gerlach says, maybe we need to add more space between the path and the file name?

[CAM-Gerlach]

Can we at least have a screenshot to see how it looks with them aligned to the right? Keeping them left might be fine, but they definitely need either more space or a separator of some sort.

[ccordoba12]

This is looking really good, thanks @juanis2112!

About @CAM-Gerlach comment, what do you think @ccordoba12 ?

I don't like this idea too much, but we can add a bit more space between the file name and its path. @juanis2112, please do that in this PR.

[ccordoba12]

@juanis2112, please update the screenshot in the PR description above to see your latest changes.

[dalthviz]

About the color used for the path, @CAM-Gerlach can you make some suggestions? Also @juanis2112 could you upload a screenshot with the light theme to see how it looks like, thanks :)

[ccordoba12]

@juanis2112, please also upload a screenshot for the light theme.

[CAM-Gerlach]

Actually, @dalthviz . #999999 may actually be the best choice after all, since the closest QDarkstyle palette color is #787878 which is even lower contrast than it is currently, when it already is at the lower limit of what I'd consider legible. I didn't realize it, but #999999 is also what we use at the comment color in the Spyder Dark theme, so it has precedent.

[dalthviz]

Thanks @juanis2112! LGTM 👍 What do you guys think @ccordoba12 @CAM-Gerlach ?

[CAM-Gerlach]

LGTM too. The path shortening behavior needs to be fixed but that's not really in scope here and I made a comment over on the issue instead. Thanks @juanis2112 !

[ccordoba12]

Looks good to me too. Thanks @juanis2112!