fix: upgrade to Angular v12

add README details

angular.json

@@ -28,7 +28,6 @@
             "main": "src/main.ts",
             "polyfills": "src/polyfills.ts",
             "tsConfig": "tsconfig.app.json",
-            "aot": true,
             "assets": [
               "src/favicon.ico",
               "src/assets"
@@ -36,7 +35,15 @@
             "styles": [
               "src/styles.scss"
             ],
-            "scripts": []
+            "inlineStyleLanguage": "scss",
+            "scripts": [],
+            "vendorChunk": true,
+            "extractLicenses": false,
+            "buildOptimizer": false,
+            "sourceMap": true,
+            "optimization": false,
+            "namedChunks": true,
+            "aot": false
           },
           "configurations": {
             "production": {