Bug: Improve warning message for ambiguous defaults

[JacobCoffee]

Description

We should enhance the warning messages generated from #3280 in 2.8.

As a user just now upgrading and hitting this, across probably ~40 instances of that warning, this isn't terribly helpful:

.venv/lib/python3.12/site-packages/litestar/typing.py:597: LitestarWarning: Ambiguous default values for annotation 'typing.Annotated[str, ParameterKwarg(examples=None, external_docs=None, content_encoding=None, default='+a', title=None, description='A string expression to filter something.', const=None, gt=None, ge=None, lt=None, le=None, multiple_of=None, min_items=None, max_items=None, min_length=None, max_length=None, pattern=None, lower_case=None, upper_case=None, format=None, enum=None, read_only=None, schema_extra=None, annotation=<_EmptyEnum.EMPTY: 0>, header=None, cookie=None, query=None, required=True)]'. The default value ''+a'' set inside the parameter annotation differs from the parameter default value '<_EmptyEnum.EMPTY: 0>'
  return cls.from_annotation(
.venv/lib/python3.12/site-packages/litestar/typing.py:597: LitestarWarning: Ambiguous default values for annotation 'typing.Annotated[bool, ParameterKwarg(examples=None, external_docs=None, content_encoding=None, default=False, title=None, description='Return something', const=None, gt=None, ge=None, lt=None, le=None, multiple_of=None, min_items=None, max_items=None, min_length=None, max_length=None, pattern=None, lower_case=None, upper_case=None, format=None, enum=None, read_only=None, schema_extra=None, annotation=<_EmptyEnum.EMPTY: 0>, header=None, cookie=None, query=None, required=None)]'. The default value 'False' set inside the parameter annotation differs from the parameter default value '<_EmptyEnum.EMPTY: 0>'
  return cls.from_annotation(

URL to code causing the issue

No response

MCVE

No response

Steps to reproduce

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Screenshots

"![SCREENSHOT_DESCRIPTION](SCREENSHOT_LINK.png)"

Logs

No response

Litestar Version

2.8

Platform

• Linux
• Mac
• Windows
• Other (Please specify in the description above)

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[github-actions]

This issue has been closed in #3378. The change will be included in the upcoming patch release.

[github-actions]

A fix for this issue has been released in v2.9.0