refactor: move most of the Windows specific code out of `hotkeywrapper.cc`

[shenlebantongying]

Plus small adjustments that have no semantic changes.

---

Why?

Google #ifdef Hell😅

It is pretty hard to understand these code with code from 3 platforms mangling together.

[shenlebantongying]

I checked out the history of win related code in the original GD.

I don't see anything useful except

• a probably accidentally deleted comment that I added back.
• an alternative implementation that have reported failures.

In the existing code, What You See Is What You Get (WYSIWYG)😅

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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