feat(pdf): refactor MinerU parsing to the official file_parse API - #3953

  import asyncio
  import time

  import httpx


  async def wait_for_mineru_ready(endpoint: str, timeout: float = 5.0) -> None:
      health_url = f"{endpoint.rstrip('/')}/health"
      deadline = time.monotonic() + timeout
      last_error = "no response"

      async with httpx.AsyncClient(timeout=0.5) as client:
          while time.monotonic() < deadline:
              try:
                  response = await client.get(health_url)
                  payload = response.json()

                  if (
                      response.status_code == 200
                      and isinstance(payload, dict)
                      and payload.get("protocol_version")
                  ):
                      return

                  last_error = (
                      f"unexpected response: HTTP {response.status_code}, "
                      f"protocol_version={payload.get('protocol_version')!r}"
                  )
              except (httpx.HTTPError, ValueError) as exc:
                  last_error = str(exc)

              await asyncio.sleep(0.2)

      raise RuntimeError(
          f"MinerU startup preflight failed for {health_url} after {timeout}s. "
          f"Last error: {last_error}. "
          "Start a compatible mineru-api service or correct
          pdf.mineru_endpoint."
      )

  pdf_config = self._config.pdf

  should_preflight_mineru = (
      pdf_config.strategy == "mineru"
      or (
          pdf_config.strategy == "auto"
          and pdf_config.mineru_endpoint is not None
      )
  )

  if should_preflight_mineru and pdf_config.mineru_endpoint:
      await wait_for_mineru_ready(pdf_config.mineru_endpoint)