change(chain): Remove Copy trait impl from Network

[idky137]

Motivation

This PR continues work towards implementing Regtest mode in Zebrad.

Removing Derive(copy) from Network is required for adding a NetworkParameters struct to Testnet. This breaks a lot of functions that take Network as an input. This PR changes these functions to take &Network where possible and clones Network where either not possible or requires significant refactoring to avoid.

Prerequisite of #7968 and part 3 of #7845.

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Solution

Removes Derive(Copy) from Network and any structs that contain Network.
Changes functions that take Network to take &Network where possible and clones network where not.

Testing

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[idky137]

conversion now complete. all tests pass (workspace wide). I'll go through the review now and make the changes requested. Ye i have been worried that its been getting big but now its complete maybe it will be possible?

[idky137]

all clippy warnings fixed and changes from review applied

[idky137]

sorry I just saw your comment about linking the commit that addresses a comment. I'll make sure to include this from now on.

[arya2]

Minor build failure: https://github.com/ZcashFoundation/zebra/actions/runs/8344331467/job/22837074445?pr=8354#step:12:4138

[idky137]

fixed build error (in commit: b09707c)

[arya2]

Let's merge it!

Thank you for the extensive changes.

[arya2]

Once it stabilizes, Ref::leak may be useful for similar cases in the future, but for now, I'm glad we were able to avoid OnceCell or being constrained to hard-coded constants. Thanks again.