Implement Standalone Android App via Flutter WebView

- Configured `vite.config.ts` for relative base path support.
- Initialized `mobile_app` Flutter project with `webview_flutter`.
- Added `assets/www` to Flutter assets configuration.
- Implemented `mobile_app/lib/main.dart` with WebView and Bridge API integration (Water Level Slider).
- Updated `.gitignore` for Flutter artifacts.
- Successfully built APK artifacts.

Co-authored-by: kliffdafunkfacekilla-arch <239708976+kliffdafunkfacekilla-arch@users.noreply.github.com>

mobile_app/assets/www/config/precreated-heightmaps.js

@@ -0,0 +1,27 @@
+"use strict";
+
+const precreatedHeightmaps = {
+  "africa-centric": {id: 0, name: "Africa Centric"},
+  arabia: {id: 1, name: "Arabia"},
+  atlantics: {id: 2, name: "Atlantics"},
+  britain: {id: 3, name: "Britain"},
+  caribbean: {id: 4, name: "Caribbean"},
+  "east-asia": {id: 5, name: "East Asia"},
+  eurasia: {id: 6, name: "Eurasia"},
+  europe: {id: 7, name: "Europe"},
+  "europe-accented": {id: 8, name: "Europe Accented"},
+  "europe-and-central-asia": {id: 9, name: "Europe and Central Asia"},
+  "europe-central": {id: 10, name: "Europe Central"},
+  "europe-north": {id: 11, name: "Europe North"},
+  greenland: {id: 12, name: "Greenland"},
+  hellenica: {id: 13, name: "Hellenica"},
+  iceland: {id: 14, name: "Iceland"},
+  "indian-ocean": {id: 15, name: "Indian Ocean"},
+  "mediterranean-sea": {id: 16, name: "Mediterranean Sea"},
+  "middle-east": {id: 17, name: "Middle East"},
+  "north-america": {id: 18, name: "North America"},
+  "us-centric": {id: 19, name: "US-centric"},
+  "us-mainland": {id: 20, name: "US Mainland"},
+  world: {id: 21, name: "World"},
+  "world-from-pacific": {id: 22, name: "World from Pacific"}
+};