feat(rpc): Implement the z_validateaddress RPC

[upbqdn]

Motivation

Close #6083.

Specifications

https://zcash.github.io/rpc/z_validateaddress.html

Solution

This PR implements the following fields:

• isvalid,
• address,
• address_type,
• is_mine.

To implement UAs, I used the zcash_address crate.

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?

[upbqdn]

An initial basic test shows that the output is identical to zcashd.

Request:
z_validateaddress t2UNzUUx8mWBCRYPRezvA363EYXyEpHokyi

Querying zebrad test chain at height >=2232411...

real    0m0.002s
user    0m0.002s
sys     0m0.000s

Querying zcashd test chain at height >=2232411...

real    0m0.002s
user    0m0.002s
sys     0m0.000s


Response diff between zebrad and zcashd:
RPC responses were identical

/tmp/tmp.ESy1lXAX0v.rpc-diff/zebrad-test-2232411-z_validateaddress.json:
{
  "isvalid": true,
  "address": "t2UNzUUx8mWBCRYPRezvA363EYXyEpHokyi",
  "address_type": "p2sh",
  "ismine": false
}

[teor2345]

This looks good, thanks for the address API changes.

We're just missing the snapshot files, so this PR will fail CI until they are added.

[codecov]

Codecov Report

Merging #6185 (be14b2d) into main (31382d2) will increase coverage by 0.01%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6185      +/-   ##
==========================================
+ Coverage   77.98%   77.99%   +0.01%     
==========================================
  Files         304      304              
  Lines       39197    39197              
==========================================
+ Hits        30568    30573       +5     
+ Misses       8629     8624       -5     

[upbqdn]

I implemented all suggestions, semantic UA checks, and I updated the PR description to reflect the new changes.

[teor2345]

I think we're missing some snapshot cases, but luckily we already have test vectors in z_listunifiedreceivers.

There might also be a minor future compatibility issue.

I don't think these are blockers to going ahead and merging this, so I'd suggest doing them in a follow-up PR.

We can also repeat the zcash-rpc-diff test on that PR.