feat: new api documentation theme

[stobrien89]

Description of changes:
Updates API doc generation. Now using PHPDocumentor for generation with a few overrides to their theming.

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[yenfryherrerafeliz]

The following two traits would need to be updated since they are failing when being parsed by the new docs tool. The return type given there is incorrect for each one. Please see below:

• EncryptionTrait the return type should be array but is has [AesStreamInterface, string]. A descriptive message can be added to note the element types for that array. Example:

* @return array An array that returns two elements as follow [AesStreamInterface, string]

• EncryptionTraitV2 the return type should be AppendStream but it has also @return [AesStreamInterface, string], and a return statement should be added at the end that handles when the condition in the switch statement is not met. Maybe return null.

[yenfryherrerafeliz]

Would it be possible to have the search result windows pops up after hitting enter? It shows up by typing just a single letter.

[stobrien89]

I have no idea what's happening with the encryption traits. I've updated the type annotations for the method, but it's still coming back with Unexpected token "[", expected type at offset 0 on line 1. Nothing appears to be wrong with either file.

The search modal position has been adjusted so it appears under the search bar. I think it's fine to show results as the search is being typed.