fixup image_pipeline_demo (backport #755)

[mergify]

Description

User's noticed (ros2/ros2_documentation#2333) that the behavior of the image_pipeline_demo related binaries in the intra_process_demo package were not behaving as depicted in the screenshots and not as described in the demo text.

This pull request was opened to fix the documentation and screenshots (ros2/ros2_documentation#5988), but I noticed and realized it was actually the demo code that was wrong and the demo documentation and screenshots were what should have been happening. I tracked it down to this commit that I made years ago that broke the expected behavior: 456b5ba

So this pull request fixed the behavior (using a unique_ptr instead of a shared_ptr in the image viewer), as well as modernizes it a bit, with better resolutions, text font size, and better window titles.

I will fixup the documentation too, with new screenshots and some slightly adjusted text to make sure everything is the way it was supposed to be. See ros2/ros2_documentation#6041

Fixes ros2/ros2_documentation#2333

Is this user-facing behavior change?

Yes, the demo should now work as intended.

Did you use Generative AI?

No.

Additional Information

As the original author of the demo, I believe this is the behavior I was intending to demonstrate here.

---

This is an automatic backport of pull request #755 done by [Mergify](https://mergify.com).

[ahcorde]

Pulls: #757
Gist: https://gist.githubusercontent.com/ahcorde/1f8d625f8327089cbe80b40a56f2905a/raw/8f16343f0b19b6fe96b3c1de73debada1a1d4665/ros2.repos
BUILD args: --packages-above-and-dependencies intra_process_demo
TEST args: --packages-above intra_process_demo
ROS Distro: jazzy
Job: ci_launcher
ci_launcher ran: https://ci.ros2.org/job/ci_launcher/17591

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