backend-common: deprecate hot reload helpers

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/wet-timers-chew.md

@@ -0,0 +1,5 @@
+---
+'@backstage/backend-common': patch
+---
+
+The `useHotCleanup` and `useHotMemoize` helpers are now deprecated, since hot module reloads for backend are being phased out.

packages/backend-common/api-report.md

@@ -785,12 +785,12 @@ export type UrlReadersOptions = {
   factories?: ReaderFactory[];
 };
 
-// @public
+// @public @deprecated
 export function useHotCleanup(
   _module: NodeModule,
   cancelEffect: () => void,
 ): void;
 
-// @public
+// @public @deprecated
 export function useHotMemoize<T>(_module: NodeModule, valueFactory: () => T): T;
 ```

packages/backend-common/src/hot.ts

@@ -47,6 +47,7 @@ function findAllAncestors(_module: NodeModule): NodeModule[] {
  * Useful for cleaning intervals, timers, requests etc
  *
  * @public
+ * @deprecated Hot module reloading is no longer supported for backends.
  * @example
  * ```ts
  * const intervalId = setInterval(doStuff, 1000);
@@ -80,6 +81,7 @@ const CURRENT_HOT_MEMOIZE_INDEX_KEY = 'backstage.io/hmr-memoize-key';
  * stateful parts of the backend, e.g. to retain a database.
  *
  * @public
+ * @deprecated Hot module reloading is no longer supported for backends.
  * @example
  * ```ts
  * const db = useHotMemoize(module, () => createDB(dbParams));