Improve Explorer Preview Panel

[onesounds]

What's the PR

• The preview shows the file size and the dates it was created and modified.
• This item can be turned on and off by the user. All three are turned on and off at once.
• General > Show details in preview area (on/off). Default is off.

ETC

• If we need more in the future, we may need to turn them on and off on a per-item basis.
  • Media Lengh...?
• We might need a separate settings page for the preview area. (not now...)
• Users may want to change the timeformat, but this is how we'll proceed for now.

Test Cases

• It should be on and off depending on settings.
• Items with no file size information(ex>folder) should not be visible at all.
• Colors should display properly even if the theme changes.

Todo

• Check ResultManager.cs logic
• Can we add folder created/modifed date? (Folder size is not considered. This is usually computationally intensive.)

[VictoriousRaptor]

IMO the implementation of preview panel should be moved to explorer plugin. it's all about files.

[Yusyuriv]

I moved the new functionality into the Explorer plugin itself.

I have a few issues with the way the date is currently displayed:

1. I think yy-M-dd date format is very confusing. It's 24-5-20 right now. I would strongly prefer yyyy-MM-dd (2024-05-20) or an option in the settings for the user to be able to customize it.
2. Same with time. hh:mm displays time in 12-hour format, but it doesn't specify AM/PM. At the very least it should display AM/PM (add tt at the end), but there's a problem: with CultureInfo.CurrentCulture, it does translate the date, but in my CurrentCulture AM/PM doesn't exist, we use 24-hour clock, so I get an empty space where AM/PM should be if I add tt in the format.

[onesounds]

Let's add the Show Toggle option and DateTimeFormat in plugin setting.

[Yusyuriv]

Time formats and date formats in Settings.cs probably need some adjustments.

[onesounds]

There's a separator color issue, which I'll fix in a separate PR. (Previously, I didn't want to add a style to the separator color, so I made it get the color from the already assigned separator. Changing to panels in this PR is causing this color to not be imported. Need to add a separate style).