GH-393: Use tiered level-1 compilation when running JVM subprocesses

[ascopes]

This PR introduces a couple of new flags in the JVM plugin scripts that enables tiered compilation that only runs at level 1 (client)
rather than level 2 (server) mode for JIT.

The idea here is to reduce the startup times for short-lived processes invoking JVM plugins internally.

Closes GH-393.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.31%. Comparing base (5739f74) to head (2d5cf6a).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #395      +/-   ##
==========================================
+ Coverage   88.10%   88.31%   +0.22%     
==========================================
  Files          33       33              
  Lines        1100     1103       +3     
  Branches       79       79              
==========================================
+ Hits          969      974       +5     
+ Misses         96       95       -1     
+ Partials       35       34       -1     

Files with missing lines	Coverage Δ
...protobufmavenplugin/plugins/JvmPluginResolver.java	89.02% <100.00%> (+0.38%)	⬆️

... and 1 file with indirect coverage changes