Heatmap solver is now a worker

- Android app now requests root (purpose still unknown)
- Android app starts on boot
- Frontend is now a PWA (purpose still unknown)

frontend/package-lock.json

@@ -554,6 +554,14 @@
         "tslib": "^2.0.0"
       }
     },
+    "@angular/service-worker": {
+      "version": "10.1.6",
+      "resolved": "https://registry.npmjs.org/@angular/service-worker/-/service-worker-10.1.6.tgz",
+      "integrity": "sha512-wGF2ZVByYonNpQNjyLn4zK0O2au1ZJQv6JLZj5zHnVnaiz/xJXvY9TPCU3dLmuRFt6UmKStLlclJkG3s3FYiZg==",
+      "requires": {
+        "tslib": "^2.0.0"
+      }
+    },
     "@babel/code-frame": {
       "version": "7.10.4",
       "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.10.4.tgz",