fix: add default value of WithCustomMessage

[samber]

No description provided.

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[Copilot]

Pull request overview

This pull request adds a new configuration option WithCustomMessage to allow users to customize the log message format for HTTP requests. The PR includes the field definition in the Config struct, sets its default value to nil, implements its usage in the logging middleware, and updates the README documentation.

Changes:

• Added WithCustomMessage field to Config struct with a function signature that accepts a ResponseWriter and Request to generate custom log messages
• Initialized the default value to nil in DefaultConfig()
• Modified the logging logic to use the custom message function when provided
• Added unrelated fail-fast: false to GitHub Actions workflow

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
middleware.go	Added WithCustomMessage field to Config struct, set default to nil, and implemented custom message logic in the logging middleware
README.md	Updated Config struct documentation to include the new WithCustomMessage field
.github/workflows/test.yml	Added fail-fast: false to test strategy (unrelated to main PR purpose)

Comments suppressed due to low confidence (1)

README.md:115

• Consider adding a usage example for the WithCustomMessage feature in the README, similar to the examples provided for other configuration options (OTEL, Custom log levels, Verbose, Filters). This would help users understand how to use the new feature effectively, especially since they would need to work with the WrapResponseWriter type to access Status(), Body(), and other methods.

	WithCustomMessage  func(w http.ResponseWriter, r *http.Request) string

	Filters []Filter
}

</details>



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[Copilot]

The function signature should use WrapResponseWriter instead of http.ResponseWriter to be consistent with the Filter type (see filters.go:10) and to provide explicit access to additional methods like Status(), Body(), and BytesWritten(). Users would need these methods to generate meaningful custom messages based on the response. Without this, users would need to perform type assertions which is not good API design.

Suggested change

	WithCustomMessage func(w http.ResponseWriter, r *http.Request) string
	WithCustomMessage func(w WrapResponseWriter, r *http.Request) string

[Copilot]

The function signature should use WrapResponseWriter instead of http.ResponseWriter to be consistent with the Filter type and to provide explicit access to additional methods like Status(), Body(), and BytesWritten(). This documentation should match the corrected type in the code.

Suggested change

	WithCustomMessage func(w http.ResponseWriter, r *http.Request) string
	WithCustomMessage func(w WrapResponseWriter, r *http.Request) string

[Copilot]

The addition of fail-fast: false to the test workflow appears unrelated to the PR's stated purpose of adding WithCustomMessage functionality. This change should either be removed from this PR or the PR description should be updated to explain why this change is included. Mixing unrelated changes can make it harder to track the purpose and impact of each change.