refactor(snap): Update command and metadata sourcing

[MonicaisHer]

• Inline CLIs flags
• Remove unused packages
• Remove external metadata sourcing
• Simplify the copying of res directory

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PR Checklist

Please check if your PR fulfills the following requirements:

• I am not introducing a breaking change (if you are, flag in conventional commit message with BREAKING CHANGE: describing the break)
• I am not introducing a new dependency (add notes below if you are)
• I have added unit tests for the new feature or bug fix (if not, why?)
• I have fully tested (add details below) this the new feature or bug fix (if not, why?)
• I have opened a PR for the related docs change (if not, why?)

Testing Instructions

New Dependency Instructions (If applicable)

[codecov-commenter]

Codecov Report

Merging #529 (4806c6b) into main (4a35f1d) will not change coverage.
The diff coverage is n/a.

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@@           Coverage Diff           @@
##             main     #529   +/-   ##
=======================================
  Coverage   21.50%   21.50%           
=======================================
  Files           5        5           
  Lines         493      493           
=======================================
  Hits          106      106           
  Misses        373      373           
  Partials       14       14           

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