fix(commit): emit deprecated warning of cz commit -s BEFORE going through dialog, add deprecation warning on cz commit --help

[bearomorphism]

Closes #1135

Description

• Now cz commit -s emits warning before the user answers the commit questions.
• Show deprecated warning on cz commit --help

Before (47beadc)

commitizen-py3.13➜  commitizen git:(master) cz c -s -- --allow-empty
? Select the type of change you are committing fix: A bug fix. Correlates with PATCH in SemVer
? What is the scope of this change? (class or file name): (press [enter] to skip)
 
? Write a short and imperative summary of the code changes: (lower case and no period)
 a
? Provide additional contextual information about the code changes: (press [enter] to skip)
 
? Is this a BREAKING CHANGE? Correlates with MAJOR in SemVer No
? Footer. Information about Breaking Changes and reference issues that this commit closes: (press [enter] to skip)
 

fix: a

signoff mechanic is deprecated, please use `cz commit -- -s` instead.
...

After

commitizen-py3.13➜  commitizen git:(signoff-fix) cz c -s -- --allow-empty
Deprecated warning: `cz commit -s` is deprecated and will be removed in v5, please use `cz commit -- -s` instead.
? Select the type of change you are committing (Use arrow keys)
 » fix: A bug fix. Correlates with PATCH in SemVer
   feat: A new feature. Correlates with MINOR in SemVer
   docs: Documentation only changes
   style: Changes that do not affect the meaning of the code (white-space, formatting, missing semi-colons, etc)
   refactor: A code change that neither fixes a bug nor adds a feature
   perf: A code change that improves performance
   test: Adding missing or correcting existing tests
   build: Changes that affect the build system or external dependencies (example scopes: pip, docker, npm)
   ci: Changes to CI configuration files and scripts (example scopes: GitLabCI)

Checklist

• I have read the contributing guidelines

Code Changes

• Add test cases to all the changes you introduce
• Run poetry all locally to ensure this change passes linter check and tests
• Manually test the changes:
  • Verify the feature/bug fix works as expected in real-world scenarios
  • Test edge cases and error conditions
  • Ensure backward compatibility is maintained
  • Document any manual testing steps performed
• Update the documentation for the changes

Steps to Test This Pull Request

• Run cz c -s -- --allow-empty to see if it works.
• Run cz c -h to see if the warning shows.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.87%. Comparing base (a9cd957) to head (c31dfc2).
Report is 6 commits behind head on refactors.

Additional details and impacted files

@@            Coverage Diff             @@
##           refactors    #1491   +/-   ##
==========================================
  Coverage      97.87%   97.87%           
==========================================
  Files             57       57           
  Lines           2677     2677           
==========================================
  Hits            2620     2620           
  Misses            57       57           

Flag	Coverage Δ
unittests	97.87% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.