Replace Squiz.Commenting.FunctionComment with new Sniff

[jaymcp]

Description

Replaces Squiz.Commenting.FunctionComment Sniff with extended version under the BigBiteDocs namespace.
Behaviourally, this new Sniff suggests int and bool as the correct type hints when doing type checking, rather than integer and boolean as in the Squiz Sniff, to adhere to Big Bite's coding standard more correctly.

We used to exclude several error codes from the Squiz Sniff, which we no longer do, now that we've introduced our version of the Sniff.
Because this is likely to result in lots of instances of the ParamCommentNotCapital and ParamCommentFullStop error codes, this PR also adds fixers for this, to make the adoption process more straightforward.

Types of changes (if applicable):

• Bug fix (non-breaking change which fixes an issue).
• New feature (non-breaking change which adds functionality).
• Breaking change (fix or feature that would cause existing functionality to not work as expected).

Checklist (if applicable):

• All checks pass when running composer run all-checks.