feat: add config option for line length warning

[Narwhal-fish]

Description

This PR implements configuration file support for the message_length_limit option, addressing issue #1571 . Previously, users could only set commit message length limits via command-line arguments (-l/--message-length-limit). Now they can define a default limit in their configuration file.

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

Documentation Changes

• Run poetry doc locally to ensure the documentation pages renders correctly
• Check and fix any broken links (internal or external) in the documentation

Expected Behavior

Users can now set default commit message length limits in their configuration file:

[tool.commitizen]
message_length_limit = 72

Steps to Test This Pull Request

1. Test Configuration File Support

# Add the following to your pyproject.toml:
[tool.commitizen]
message_length_limit = 30

# Test with long message (should fail)
cz check -m "fix: this is a very long commit message that exceeds 30 characters"

# Test with short message (should pass)  
cz check -m "fix: short message"

2. Test CLI Override

# CLI argument should override config setting
cz check -m "fix: this message is longer than 30 chars but shorter than 60" -l 60

# Disable limit with CLI
cz check -m "fix: very long message that would normally fail config limit" -l 0

Additional Context

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (v4-9-2@e63600b). Learn more about missing BASE report.

Additional details and impacted files

@@            Coverage Diff            @@
##             v4-9-2    #1574   +/-   ##
=========================================
  Coverage          ?   98.71%           
=========================================
  Files             ?       60           
  Lines             ?     2655           
  Branches          ?        0           
=========================================
  Hits              ?     2621           
  Misses            ?       34           
  Partials          ?        0           

Flag	Coverage Δ
unittests	98.71% <100.00%> (?)

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[Narwhal-fish]

Sorry, I accidentally closed this pull request.

[Lee-W]

let's rebase from v4-9-test

[Narwhal-fish]

I have rebased my branch onto v4-9-0.
I’m not very familiar with Git, so please let me know if I missed anything.

[Lee-W]

I have rebased my branch onto v4-9-0. I’m not very familiar with Git, so please let me know if I missed anything.

You've done it perfectly 🙂 I'll take a look when bandwidth allow

[bearomorphism]

Thanks! A few suggestion:

[Lee-W]

we might need to resolve the conflict first. Thanks!

[bearomorphism]

Hi @Narwhal-fish , could you help to rebase your branch when you have a moment?

You can run

git fetch upstream
git rebase upstream master -i

and then drop all commits but yours.