Split sharp bits documentation page into 3 pages

[josh146]

Context: The sharp bits documentation page is getting a little too long

Description of the Change:

The page has been split up into:

• Callbacks + GPUs
• Jax integration
• Sharp bits (everything else)

Benefits: Much easier to navigate and find what you're looking for. In particular, JAX integration and callbacks aren't really 'sharp bits', so don't really belong on that page.

Possible Drawbacks: n/a

Related GitHub Issues: n/a

[sc-60492] # Documentation for running callbacks on GPUs

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