Go generator template: provide ability to perform non-error flag evaluation

[sahidvelji]

cli/internal/generators/golang/golang.tmpl

Lines 10 to 19 in f260209

	type BooleanProvider func(ctx context.Context, evalCtx openfeature.EvaluationContext) (bool, error)
	type BooleanProviderDetails func(ctx context.Context, evalCtx openfeature.EvaluationContext) (openfeature.BooleanEvaluationDetails, error)
	type FloatProvider func(ctx context.Context, evalCtx openfeature.EvaluationContext) (float64, error)
	type FloatProviderDetails func(ctx context.Context, evalCtx openfeature.EvaluationContext) (openfeature.FloatEvaluationDetails, error)
	type IntProvider func(ctx context.Context, evalCtx openfeature.EvaluationContext) (int64, error)
	type IntProviderDetails func(ctx context.Context, evalCtx openfeature.EvaluationContext) (openfeature.IntEvaluationDetails, error)
	type StringProvider func(ctx context.Context, evalCtx openfeature.EvaluationContext) (string, error)
	type StringProviderDetails func(ctx context.Context, evalCtx openfeature.EvaluationContext) (openfeature.StringEvaluationDetails, error)
	type ObjectProvider func(ctx context.Context, evalCtx openfeature.EvaluationContext) (any, error)
	type ObjectProviderDetails func(ctx context.Context, evalCtx openfeature.EvaluationContext) (openfeature.InterfaceEvaluationDetails, error)

The Go SDK provides three methods for flag evaluation for each type:

• https://pkg.go.dev/github.com/open-feature/go-sdk@v1.16.0/openfeature#Client.Boolean
• https://pkg.go.dev/github.com/open-feature/go-sdk@v1.16.0/openfeature#Client.BooleanValue
• https://pkg.go.dev/github.com/open-feature/go-sdk@v1.16.0/openfeature#Client.BooleanValueDetails

The CLI should support all three.