chore: create internal method for subscribing to subscription state changes

[steveluscher]

Problem

In #28290 we need to be able to wait on an onSignature subscription having been established, after which we do more work.

Summary of Changes

• Create an internal method of tracking the state of every subscription.

[codecov]

Codecov Report

Merging #28525 (d39b3fc) into master (831ed96) will decrease coverage by 0.1%.
The diff coverage is 53.3%.

❗ Current head d39b3fc differs from pull request most recent head e6672e8. Consider uploading reports for the commit e6672e8 to get more accurate results

@@            Coverage Diff            @@
##           master   #28525     +/-   ##
=========================================
- Coverage    77.1%    77.0%   -0.2%     
=========================================
  Files          55       55             
  Lines        2934     2956     +22     
  Branches      408      414      +6     
=========================================
+ Hits         2264     2278     +14     
- Misses        529      536      +7     
- Partials      141      142      +1     

[steveluscher]

This ended up being merged as part of #28290 because GitHub is great at doing stacked PRs.