v5: chore!: drop CJS support and related tooling

[BlankParticle]

This PR is supposed to be targeted to the branch for hono v5, which doesn't exists yet.
I am making this PR to start off the work for Hono v5, so that we can start merging things into the v5 branch one by one.

Once we have a v5 branch, change the the base for this PR to that branch
resolves #5105

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.04%. Comparing base (44f8843) to head (edb938c).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5114   +/-   ##
=======================================
  Coverage   79.04%   79.04%           
=======================================
  Files         154      154           
  Lines       10779    10779           
  Branches     2256     2256           
=======================================
  Hits         8520     8520           
  Misses       2259     2259           

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