feat: use dummy pusher by default

[a3d21]

Default to using DummyPusher.

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[sweep-ai]

Apply Sweep Rules to your PR?

• Apply: All new business logic should have corresponding unit tests.
• Apply: Refactor large functions to be more modular.

[codecov]

Codecov Report

Merging #1349 (dc03be5) into main (1aef30d) will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##            main   #1349   +/-   ##
=====================================
  Coverage   2.41%   2.41%           
=====================================
  Files         13      13           
  Lines        786     786           
=====================================
  Hits          19      19           
  Misses       764     764           
  Partials       3       3