Allow float width/height in document page Size

[Dinwid]

Problem

GET /document/{document_id} can return non-integer page dimensions in pages[].size, e.g.:

"pages": [
  {
    "src": "...",
    "size": { "width": 612, "height": 791.99 }
  }
]

Since Size is declared under strict_types=1 with int constructor parameters, Size::fromArray() throws an uncatchable-in-practice TypeError whenever the API returns a float, which breaks DocumentGet deserialization for such documents.

Fix

Widen width/height in SignNow\Api\Document\Response\Data\Size from int to float|int (constructor and getters). Integer values keep round-tripping as integers through toArray(); float values no longer fatal.

phpcs passes on the changed file.