Add initial ActionState type

Author: mbg

src/action-common.ts

@@ -0,0 +1,14 @@
+import { Env } from "./environment";
+import { FeatureEnablement } from "./feature-flags";
+import { Logger } from "./logging";
+
+export interface ActionState {
+  /** The logger that is in use. */
+  logger: Logger;
+
+  /** Information about environment variables. */
+  env: Env;
+
+  /** Information about enabled feature flags. */
+  features: FeatureEnablement;
+}