ValidationScheme implements pflag.Value and json.Marshaler/Unmarshaler interfaces

[juliusmh]

No description provided.

[aknuds1]

I don't understand why you're removing the fmt.Stringer assertion.

[Copilot]

Pull Request Overview

This PR implements additional interfaces for the ValidationScheme type to support JSON marshaling/unmarshaling and command-line flag parsing. The changes enhance the ValidationScheme type by making it compatible with JSON serialization and pflag.Value interface for CLI usage.

Key changes:

• Added JSON marshaling and unmarshaling support for ValidationScheme
• Implemented pflag.Value interface methods (Set and Type)
• Refactored existing YAML unmarshaling to use the new Set method for consistency

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
model/metric.go	Implements JSON marshaling/unmarshaling and pflag.Value interface methods for ValidationScheme
model/metric_test.go	Adds comprehensive test coverage for new JSON and pflag functionality

[Copilot]

The comment 'Don't change the value' is misleading for an empty string input. When Set() is called with an empty string, it should set the value to UnsetValidation, not leave it unchanged. Either update the logic to set *s = UnsetValidation or clarify the comment to explain why empty strings preserve the current value.

Suggested change

	// Don't change the value.
	// Set to UnsetValidation for empty string input.
	*s = UnsetValidation

Stale.