feat: ESSR tunneling with KERIA API

[iFergal]

This will require a new dev release after WebOfTrust/keria#351 is merged, but locally all the integration tests pass.

HTTP requests between Signify and KERIA are now wrapped/tunneled in ESSR (encrypted HTTP request inside the body of a signed wrapper HTTP request) for confidentiality and general improvements.

createSignedRequest can still be used to use the old method of signed headers in case any projects or extensions are using that for web interactions.

[codecov]

Codecov Report

Attention: Patch coverage is 99.21260% with 1 line in your changes missing coverage. Please review.

Project coverage is 84.01%. Comparing base (cddb007) to head (a214c0c).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/keri/app/clienting.ts	96.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #304      +/-   ##
==========================================
+ Coverage   83.64%   84.01%   +0.36%     
==========================================
  Files          48       48              
  Lines        4238     4328      +90     
  Branches     1042     1064      +22     
==========================================
+ Hits         3545     3636      +91     
+ Misses        663      662       -1     
  Partials       30       30              

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[edeykholt]

@iFergal Great to see this security hardening!

Since Authenticater / Authenticator is exported and its spelling changed, this might suggest a version change?

Note that WebCrypto in Chrome browser will soon support X25519, so when that's available, it might be a more performant alternative to libsodium when signify-ts is used in browser extensions. Could be a separate backlog item to abstract the crypto library interface.
[X25519 algorithm of the Web Cryptography API](https://chromestatus.com/feature/6291245926973440)