Implement runtime package for creating runtime CLI

Signed-off-by: Evan Lezar <elezar@nvidia.com>

internal/runtime/api.go

@@ -0,0 +1,33 @@
+package runtime
+
+type rt struct {
+	logger       *Logger
+	modeOverride string
+}
+
+// Interface is the interface for the runtime library.
+type Interface interface {
+	Run([]string) error
+}
+
+// Option is a function that configures the runtime.
+type Option func(*rt)
+
+// New creates a runtime with the specified options.
+func New(opts ...Option) Interface {
+	r := rt{}
+	for _, opt := range opts {
+		opt(&r)
+	}
+	if r.logger == nil {
+		r.logger = NewLogger()
+	}
+	return &r
+}
+
+// WithModeOverride allows for overriding the mode specified in the config.
+func WithModeOverride(mode string) Option {
+	return func(r *rt) {
+		r.modeOverride = mode
+	}
+}