build(android): build from web/ instead of the loto submodule

web/ and android/ now live in one repository, so the pinned submodule at
android/loto is redundant. Point Capacitor's webDir and the build script at
../web directly, and drop the pin-bumping workflow from the docs.

android/capacitor.config.json

@@ -1,7 +1,7 @@
 {
   "appId": "com.miti99.loto",
   "appName": "Lo To",
-  "webDir": "loto/build",
+  "webDir": "../web/build",
   "server": {
     "androidScheme": "https"
   }