Auto-deduce valid values for enum @Option fields

[timtebeek]

Summary

• When an @Option annotation does not explicitly specify valid values and the annotated type is an enum, the valid values are now automatically populated from the enum constants via reflection.
• Adds a private validValues() helper in Recipe.java used by all three option discovery paths (field, getter method, constructor parameter).
• Explicit valid values on the annotation still take precedence over auto-deduction.

Test plan

• Added tests for enum options on fields, getter methods, and constructor parameters
• Added test verifying explicit valid takes precedence over enum constants
• All existing RecipeBasicsTest tests continue to pass

[timtebeek]

I noticed we're not always remembering to set the valid values correctly; e.g.

rewrite/rewrite-maven/src/main/java/org/openrewrite/maven/IncrementProjectVersion.java

Lines 53 to 63 in 317e4b9

	@Option(displayName = "Semver digit",
	description = "`MAJOR` increments the first digit, `MINOR` increments the second digit, and `PATCH` " +
	"increments the third digit.",
	example = "PATCH")
	SemverDigit digit;
	public enum SemverDigit {
	MAJOR,
	MINOR,
	PATCH
	}

Which then results in an awkward text field:

This ensures we get all values exposed unless there's an explicit override.