fix: migrate to using sink modules

Deprecate the built-ins

.npmrc

@@ -1 +1,2 @@
 package-lock=false
+save-exact=true

lib/main.js

@@ -1,3 +1,6 @@
+import FS from '@eik/sink-file-system';
+import MEM from '@eik/sink-memory';
+
 import VersionsGet from './handlers/versions.get.js';
 import AliasPost from './handlers/alias.post.js';
 import AliasPut from './handlers/alias.put.js';
@@ -11,8 +14,6 @@ import MapGet from './handlers/map.get.js';
 import MapPut from './handlers/map.put.js';
 
 import TEST from './sinks/test.js';
-import MEM from './sinks/mem.js';
-import FS from './sinks/fs.js';
 
 import HealthCheck from './utils/healthcheck.js';
 import globals from './utils/globals.js';
@@ -31,9 +32,23 @@ const http = {
     MapPut,
 };
 
+/**
+ * @deprecated The built-in sinks will be removed in a future version of core.
+ * Install the sink you want as a dependency and pass it as an option when constructing the Service.
+ * Ex: sink.MEM is replaced by eik/sink-memory. sink.FS is replaced by eik/sink-file-system.
+ */
 const sink = {
+    /**
+     * @deprecated Import eik/sink-memory or implement your own and pass it to the Service instead.
+     */
     TEST,
+    /**
+     * @deprecated Import eik/sink-memory and pass it to the Service instead
+     */
     MEM,
+    /**
+     * @deprecated Import eik/sink-file-system and pass it to the Service instead
+     */
     FS,
 };
 
@@ -49,4 +64,4 @@ export default {
     http,
     sink,
     prop,
-}
+};