make pwa for offline usage

package-lock.json

@@ -19,6 +19,7 @@
         "@angular/platform-browser-dynamic": "^19.0.0",
         "@angular/platform-server": "^19.0.0",
         "@angular/router": "^19.0.0",
+        "@angular/service-worker": "^19.0.0",
         "@angular/ssr": "^19.0.2",
         "express": "^4.18.2",
         "rxjs": "~7.8.0",
@@ -602,6 +603,25 @@
         "rxjs": "^6.5.3 || ^7.4.0"
       }
     },
+    "node_modules/@angular/service-worker": {
+      "version": "19.0.1",
+      "resolved": "https://registry.npmjs.org/@angular/service-worker/-/service-worker-19.0.1.tgz",
+      "integrity": "sha512-A4sXkytnG8XYYochzBsXgQgfBUWgHbQEJkmzQ+E00hbymmgzI5y2BCW56HeI8riiIUAfrgXhfzZobdI+/h72jg==",
+      "license": "MIT",
+      "dependencies": {
+        "tslib": "^2.3.0"
+      },
+      "bin": {
+        "ngsw-config": "ngsw-config.js"
+      },
+      "engines": {
+        "node": "^18.19.1 || ^20.11.1 || >=22.0.0"
+      },
+      "peerDependencies": {
+        "@angular/common": "19.0.1",
+        "@angular/core": "19.0.1"
+      }
+    },
     "node_modules/@angular/ssr": {
       "version": "19.0.2",
       "resolved": "https://registry.npmjs.org/@angular/ssr/-/ssr-19.0.2.tgz",