fix(panic): Stop panicking on async task cancellation on shutdown in network and state futures

[teor2345]

Motivation

We want to stop Zebra panicking on shutdown.

Close #7170

Specifications

Threads:
https://doc.rust-lang.org/std/thread/struct.JoinHandle.html#method.is_finished

Async tasks:
https://docs.rs/tokio/latest/tokio/task/struct.JoinHandle.html#impl-Future-for-JoinHandle%3CT%3E
https://docs.rs/tokio/latest/tokio/task/struct.JoinError.html#method.try_into_panic

Complex Code or Requirements

This PR replaces a bunch of complex panic-handling code with consistent trait methods.

Solution

• Create generic traits for checking and waiting for panics
• Implement those traits on OS threads and async tasks
• Use those trait impls to fix the panic and cancel bugs
• Replace existing manual implementations with the trait impls

Testing

I've changed enough impls in this PR that any bugs should show up in the tests as they shut Zebra down.

Review

This is a routine bug fix.

Reviewer Checklist

• Will the PR name make sense to users?
  • Does it need extra CHANGELOG info? (new features, breaking changes, large changes)
• Are the PR labels correct?
• Does the code do what the ticket and PR says?
  • Does it change concurrent code, unsafe code, or consensus rules?
• How do you know it works? Does it have tests?

Follow Up Work

We can use these methods on JoinError and JoinHandle throughout Zebra, or maybe create our own JoinHandle and JoinError types that automatically use these methods.

[arya2]

This looks great, thank you for the simplification!