fix(metro-service): add RAM bundle deprecation warning (#3350)

.changeset/cold-eggs-poke.md

@@ -0,0 +1,8 @@
+---
+"@rnx-kit/metro-service": patch
+---
+
+RAM bundle is deprecated and was removed in 0.75. This command may stop working
+altogether in the future.
+
+For more details, see https://github.com/facebook/react-native/pull/43292.

packages/metro-service/src/ramBundle.ts

@@ -1,3 +1,4 @@
+import { warn } from "@rnx-kit/console";
 import type { ConfigT } from "metro-config";
 import * as path from "path";
 import type { BundleArgs } from "./bundle";
@@ -5,6 +6,10 @@ import { bundle } from "./bundle";
 import { requireMetroPath } from "./metro";
 
 export function ramBundle(args: BundleArgs, config: ConfigT): Promise<void> {
+  warn(
+    "RAM bundle is deprecated and was removed in 0.75; for more details, see https://github.com/facebook/react-native/pull/43292"
+  );
+
   const ramBundlePath = path.join(
     requireMetroPath(config.projectRoot),
     "src",