Binary sv2 cleanup

[Shourya742]

closes: #2171 #2173 #2175 #2176 #2177 #2178 #2179

Apart from the issues mentioned above, this PR introduces several additional improvements:

1. Removes a significant amount of redundant code.
2. Expands the API surface. In particular, conversions for copy types are now lossless, while conversions for variable-sized types are performed through TryFrom. (More details can be found in the companion sv2-apps PR. I'm open to suggestions for alternative APIs these additions are primarily based on my experience working with the sv2-apps codebase.)
3. Introduces a dedicated MAC type, bringing us into full compliance with the specification.
4. Replaces a large number of handwritten From implementations with MBE macros, significantly reducing duplication.
5. Fixes issues in the streaming APIs. Previously, certain code paths could lead to unbounded reads, creating potential attack vectors. Reads are now properly bounded, and recursion-related bounds have been removed from the writer implementation.
6. Removes U32Ref and U8Owned, as they do not provide any meaningful structural advantages.
7. Adds iterator support for Seq types, allowing users to iterate over elements and perform in-place modifications more ergonomically.

companion stratum-mining/sv2-apps#576

[Shourya742]

Awesome, the test are passing, atleast I have not broken any invariants. Need to improve API ergonomics and should be good to go.

[Shourya742]

I will open issues for all the extra points mentioned in the description.