refactor: reorganize component files and update import paths; add PsItem and PsProduct interfaces

client/package.json

@@ -3,7 +3,7 @@
   "version": "0.0.0",
   "scripts": {
     "ng": "ng",
-    "start": "ng serve",
+    "start": "ng serve --proxy-config proxy.conf.json",
     "build": "ng build",
     "watch": "ng build --watch --configuration development",
     "test": "ng test"
@@ -37,4 +37,4 @@
     "karma-jasmine-html-reporter": "~2.1.0",
     "typescript": "~5.5.2"
   }
-}
+}