refactor!: move param helpers to g-c-http-client

[coryan]

The parameter helpers are only used by HTTP+JSON clients, and then only
as implementation details.

Part of the work for #1490

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.36%. Comparing base (e66ce91) to head (3663d15).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1507   +/-   ##
=======================================
  Coverage   95.36%   95.36%           
=======================================
  Files          38       38           
  Lines        1576     1576           
=======================================
  Hits         1503     1503           
  Misses         73       73           

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