fix(app): prepare for update

.browserslistrc

@@ -0,0 +1,12 @@
+# This file is used by the build system to adjust CSS and JS output to support the specified browsers below.
+# For additional information regarding the format and rule options, please see:
+# https://github.com/browserslist/browserslist#queries
+
+# You can see what browsers were selected by your queries by running:
+#   npx browserslist
+
+> 0.5%
+last 2 versions
+Firefox ESR
+not dead
+IE 11

tsconfig.base.json

@@ -0,0 +1,24 @@
+{
+  "compileOnSave": false,
+  "compilerOptions": {
+    "importHelpers": true,
+    "module": "es2020",
+    "outDir": "./dist/out-tsc",
+    "sourceMap": true,
+    "declaration": false,
+    "moduleResolution": "node",
+    "emitDecoratorMetadata": true,
+    "experimentalDecorators": true,
+    "target": "es2015",
+    "typeRoots": [
+      "node_modules/@types"
+    ],
+    "lib": [
+      "es2017",
+      "dom"
+    ],
+    "plugins": [
+      { "name": "tslint-language-service"}
+    ]
+  }
+}