chore(chat): make subcommands independent of commands

[Konippi]

Issue #, if available:
N/A
to ensure flexibility for feature functions (e.g., #1804)

Description of changes:
By separating subcommand from command,
this PR makes it possible to flexibly implement to future functions.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[brandonskiser]

Testing this and it doesn't seem to work - /profile h and pressing tab doesn't complete to the help subcommand, and instead does a fallback to the file system. Have you verified locally?

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 16.75%. Comparing base (d4e9350) to head (2af5ee6).
Report is 27 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1806   +/-   ##
=======================================
  Coverage   16.75%   16.75%           
=======================================
  Files         213      213           
  Lines       20704    20704           
  Branches      871      871           
=======================================
  Hits         3468     3468           
  Misses      17236    17236           

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[Konippi]

Testing this and it doesn't seem to work - /profile h and pressing tab doesn't complete to the help subcommand, and instead does a fallback to the file system. Have you verified locally?

I tried verifying it in my local environment.
I didn't implement subcommand completion because just refactoring for flexible code changes that would occur in the future. Probably the subcommand completion feature is not supported in the current version either...