chore: php remediations

[justlevine]

What

This is a first pass of PHPStan/PHPCS remediations. Most were auto-fixed, a couple (like moving the file headers above the declare_strict() ),

Some tweaks to the phpcs.xml.dist as well, due to some accidental conflicts when I was deduping rulesets.

Follow up to #4

Remaining smells are:

• WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedFunctionFound - do we want a namespace?
• WordPress.WP.I18n.MissingArgDomain - do we want this translatable before merged into core?
• Missing array shapes - I just didnt have time right now to review the APIs and add them it but this is easy to do.

And then some things that need actual remediation (using WP_Ability as a string) or a decision about if we want to suppress/fix/turn off the rule.

Why

1. In its current shape, it incrementally remediates making the "noise smaller" (and the merge conflicts fewer)
2. Lets us visually deliberate about rules we may or may not care about.

[codecov]

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[gziolo]

That's a nice improvement. We can address the rest of reported issues in follow-up PRs. I like how it helps to catch some small things in the code 💯

[gziolo]

And then some things that need actual remediation (using WP_Ability as a string) or a decision about if we want to suppress/fix/turn off the rule.

This was an actual error that I fixed in f762155.