docs: [DocumentAi] Regenerated REST and RPC Document AI documentation to include missing changes from September 2024 to November 2025 (#8878)

* docs: Regenerated REST and RPC Document AI documentation to include missing changes from September 2024 to November 2025
docs: Fixed language issues in multiple message field descriptions

PiperOrigin-RevId: 859310712

Source-Link: googleapis/googleapis@64f7880

Source-Link: googleapis/googleapis-gen@fb3128f
Copy-Tag: eyJwIjoiRG9jdW1lbnRBaS8uT3dsQm90LnlhbWwiLCJoIjoiZmIzMTI4ZjRlNTg4NjJkMGUzM2VmNTUxMGViM2NjNDMzMzJiYWE1ZCJ9

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

---------

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: gcf-owl-bot[bot]