Add more information from response object to APIError during file upload

[avnermay]

Not much information is currently shared when there is an error during file upload. Adding more info from response object.

I copied the way the APIError was created here:

together-python/src/together/filemanager.py

Lines 259 to 262 in 64d0067

	raise APIError(
	f"Unexpected error raised by endpoint: {response.content.decode()}, headers: {response.headers}",
	http_status=response.status_code,
	)

Fixes #ENG-25010