Issue #3617545: Migrate off the deprecated helper wrappers, raise PHPStan to 3

Move the module's own 167 remaining calls off the deprecated MyrestHelper facades onto the services those facades delegate to, and drop the ignore pattern that hid them. The resources get the eight structure services in create(); the normalizer and the paragraph builder take theirs as constructor arguments.

Then level 1 to 3. The named field accessors now return what their names promise, and filter the references so the promise holds; thirteen @var tags that sat on the line before the assignment were moved onto it or dropped; the redirect entity is type-hinted as one, and two getType() calls on a loaded entity became bundle().

Two bugs the analysis surfaced: a default image reported an empty alt, an empty title and image_id 0, because those were read off the file entity instead of the field setting; and two variables were annotated as a paragraphs storage interface that does not exist.

Closes #3617545