feat: rocksdb (persistent) transaction status cache

[sunnygleason]

Problem

• we need to cache transaction status (Ok() | TransactionError) to return via RPC 📡 (see Implement getConfirmedBlock RPC method #6867)

Summary of Changes

• add a transaction status column family to rocksdb keyed by (slot, hash) 🏦

Open Issues

• We can use the int equivalent of the TransactionError enum; however, that is vulnerable to future code changes that change enum value indices. Should we use a more change-resistant value or technique for the status code?

Fixes # N/A (potentially multiple)

[sunnygleason]

(@CriesofCarrots FYI)

[mvines]

We can use the int equivalent of the TransactionError enum; however, that is vulnerable to future code changes that change enum value indices. Should we use a more change-resistant value or technique for the status code?

Using TransactionError is ok IMO. This is just another facet of our binary ABI that will cause a hard fork if ever changed in a way that is not backwards compatible after mainnet launch

[CriesofCarrots]

Using TransactionError is ok IMO

Yeah, my thinking was to use transaction::Result<()>

[codecov]

Codecov Report

Merging #6958 into master will increase coverage by 4.1%.
The diff coverage is 81.2%.

@@           Coverage Diff            @@
##           master   #6958     +/-   ##
========================================
+ Coverage    74.7%   78.8%   +4.1%     
========================================
  Files         223     223             
  Lines       45245   42924   -2321     
========================================
+ Hits        33815   33845     +30     
+ Misses      11430    9079   -2351

[sunnygleason]

@CriesofCarrots ok, I think this is worth a look -- looking forward to your feedback!

[sunnygleason]

🎉

[CriesofCarrots]

One nit, one suggestion, then let's