Installation guide improvements (especially for Windows)

[stevapple]

This PR refines the installation guides to make it nicer and clearer, especially for Windows.

Motivation:

The Windows installation guide now have WinGet and Scoop part messed up. Different installation options should be arranged into separate source files like the Linux ones.

Modifications:

• Splits _winget.md, _scoop.md and _traditional.md from /install/windows/index.md;
• Fixes various typos in /install;
• Updates Python installation instruction;
• Adds back some documentation pieces that were dropped accidentally;
• Fixes code highlighting for CMD (batch instead of cmd) and PowerShell (powershell instead of pwsh);
• Aligns the styling within installation guides;
• Removes duplicated contents in /download that are referenced nowhere.

Result:

• The /install/windows page is updated for accuracy and appearance, and the sources are structured more clearly.
• macOS and Linux guides are slightly improved.
• Unused duplicated contents in /download are removed.

[stevapple]

CC @shahmishal. This PR is marked as draft simply because I didn’t build and preview it yet.

[shahmishal]

This looks great, I would also like to have @compnerd review the changes.

[stevapple]

Screenshot

[compnerd]

First of all, I really like the splitting up of the rules into individual files. This makes it way better.

Secondly, I like the touch up with the warning class, it highlights those bits better.

Aside from the minor editorial bit, the Windows changes are a welcome change and look good to me.

[shahmishal]

@swift-ci test

[stevapple]

Anyone to merge?

[stevapple]

@shahmishal @compnerd Can you help to merge this?

[compnerd]

@stevapple I wish I could, but I don't have that right. Mishal is out for a bit. Perhaps @tomerd can help?

[tomerd]

I'll let @shahmishal merge when back

[stevapple]

We see increased numbers of posts regarding Windows installation on Swift Forums these days, so I wonder if @shahmishal can be back soon to avoid more users being confused. If Mishal is not available in a short time, may @tomerd merge it on behalf?

[shahmishal]

LGTM! Thanks

[KimTheLearner]

Thanks for all this great work! @shahmishal and @stevapple, if it's not too late, might you have a look at these and consider?

• my items 1 and 2 described in Order of installs for Windows is not specified #286 (item 3 was addressed 😄)
• Python notes in Traditional Instructions for Windows need corrections #287
• Might it be possible to make the footprint a bit leaner, for the Windows installation? #289

or reply as to why they won't be addressed?

Also, prior to the recent changes, the Getting Started page had an example of using LLDB, as part of the install. Did that get dropped? if so, could it be restored? Or, where did that get moved to?

Thanks!

[tomerd]

cc @compnerd @stevapple ^^