Rewrite some @GlobalScope keys in documentation to use [code] tags

[Mickeon]

Fixes godotengine/godot-docs#8127

This PR changes the descriptions of some @GlobalScope Key constants to be a bit more elaborate and use [code] tags, instead of beginning with the symbol. This not only prevents the symbols from accidentally being used for formatting, but allows the descriptions to be localized a lot better.
In the meantime, keywords are also added to the affected keys.

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This PR originally was going to use [kbd] tags across ALL Keys. However, the idea fell through.
Content in [kbd] tags is assumed to be untranslatable, as the engine does not localize keycode text. It also oftentimes made readability worse (for the sake of accuracy), and would've been a massive change for a somewhat cosmetic change. This can be reconsidered another time.

[Mickeon]

In US English this is commonly known as an "Exclamation point". however, for consistency with the surrounding descriptions, I'd rather personally call it "Exclamation mark". Feel free to argue against this.

[tetrapod00]

Both seem perfectly fine to me as a native American English speaker. I don't think the American English standard that Godot uses needs to apply to the choice of terms to use, it's mostly important to standardize spelling

[aaronfranke]

I'm from the US (lived in CA, TX, NC) and I've only ever heard it referred to as "Exclamation mark".

[Repiteo]

Midwest perspective: I've most commonly heard either "Exclamation Point" or simply "Exclamation;" while comparatively uncommon, it's obvious what "Exclamation Mark" is referring to & it does fit better overall

[tetrapod00]

(Assuming that Mickeon knows what they're doing with formatting) Good as-is, left some optional comments

[tetrapod00]

Both seem perfectly fine to me as a native American English speaker. I don't think the American English standard that Godot uses needs to apply to the choice of terms to use, it's mostly important to standardize spelling

[tetrapod00]

Suggested change

	Vertical bar ([code]|[/code]) key.
	Vertical bar or pipe ([code]|[/code]) key.

Potentially?

For some reason it seems weird to not use the name as it appears in the enum itself. But I also see the logic of only including one name for the character, and choosing the most popular one, even if it's not the one in the enum itself.

[Mickeon]

I was going to add things along the lines of "also known as...", but I believed it to be out of scope of this PR, or potentially be just a bit too verbose for my tastes.

[Mickeon]

Addressed @akien-mga 's keyword issue.

[aaronfranke]

Looks good, but I would personally prefer to mention the word "pipe" directly in the description of |, and "hash" for #. These are arguably the more common names, though not the official ones according to Wikipedia.

[Mickeon]

As @tetrapod00 also wanted, I updated the PR to also mention both of the above.

[akien-mga]

I still don't understand why we're using "snake_case" keywords here?

Keywords are related words that users might type in the search bar. They're meant to be natural language, not pseudo API.

I would just put "round bracket left" as a keyword, or no keywords.

[Mickeon]

Unsure now that I think about it, it's just been convention. Keywords don't really rely on the underscore

[Mickeon]

Updated the PR. Because they're not in snake_case anymore, I believed it was worth rewriting the "left" and "right" bracket keywords to be "open" and "close", respectively.

[Repiteo]

Thanks!