fix(examples): bound image telephone downloads

[Ghraven]

Problem

The image-telephone examples download generated image URLs with requests.get(image_url).content. Without a timeout, the examples can hang indefinitely if the image host stalls. They also write the response body without checking HTTP status, so an error response can be saved as if it were an image.

Before / after

Before, both the base image-telephone example and the Hamilton integration variant used unbounded image downloads and did not call raise_for_status().

After, both examples use a 30 second image download timeout and call raise_for_status() before writing the image bytes. Successful downloads keep the same behavior.

Verification

• python -m py_compile examples\image-telephone\application.py examples\integrations\hamilton\image-telephone\application.py
• git diff --check