Add draw() method to trigger pipeline image visualization

[bilgeyucel]

Is your feature request related to a problem? Please describe.
The pipeline image shows up when the add_component and connect methods are called. This is sometimes problematic because:

• The image takes up a lot of space
• Sometimes, the image creation raises an error as the mermaid service can be unstable from time to time

Describe the solution you'd like
Change the behavior of pipeline images showing up by default and add show() method to visualize those images when required

Describe alternatives you've considered
Just change the default behavior and not provide a show() method (we already have draw() method to visualize the image)

Additional context
N/A

[masci]

I think we just need to turn off this auto-show feature: https://github.com/deepset-ai/haystack/blob/main/haystack/core/pipeline/pipeline.py#L91-L94 - not sure I get what the difference would be between draw/show?