feat: Add click ParamType to handle JSON parsing

[tpoliaw]

Argument parsing has been moved into a click option validator. This
lets clicks error handling deal with invalid JSON being passed to the
run_plan method instead of having it with the rest of the run logic.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.15%. Comparing base (ddc3f2a) to head (fc3d25b).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1080      +/-   ##
==========================================
- Coverage   95.18%   95.15%   -0.03%     
==========================================
  Files          43       43              
  Lines        3009     3016       +7     
==========================================
+ Hits         2864     2870       +6     
- Misses        145      146       +1     

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[DiamondJoseph]

Nothing blocking so approving but had some comments

[RJCD-Diamond]

Please let me know before this change is merged, because this will break things for me

[DiamondJoseph]

Removed my +2 and added the 2.0 label so it shouldn't get merged without consideration (already had feat!)

[tpoliaw]

Updated onto recent changes. Change is now limited to the CLI and is no longer breaking. There doesn't seem to be any non-CLI logic left in the CLI though so I think this still closes the original issue.

[abbiemery]

Appears to run plans and also raise errors when I expect it to.