update program entry point docs

Author: guybedford

doc/api/cli.md

@@ -33,7 +33,8 @@ If a file is found, its path will be passed to the
 
 * The program was started with a command-line flag that forces the entry
   point to be loaded with ECMAScript module loader, such as `--import`.
-* The file has an `.mjs` extension.
+* The file has an `.mjs`, `.mts` (with `--experimental-strip-types`) or `.wasm`
+  (with `--experimental-wasm-modules`) extension.
 * The file does not have a `.cjs` extension, and the nearest parent
   `package.json` file contains a top-level [`"type"`][] field with a value of
   `"module"`.