Expo app: native front end for health.rehbock.xyz

Login (HTTP Basic, token in SecureStore) + Today, Blood, Sleep, Train,
Body, Mind, DNA screens ported from the PWA at /app/. All data is
fetched live from health.rehbock.xyz; nothing is stored on device
beyond the auth token.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app.json

@@ -1,18 +1,22 @@
 {
   "expo": {
-    "name": "health-app",
+    "name": "Health",
     "slug": "health-app",
     "version": "1.0.0",
     "orientation": "portrait",
     "icon": "./assets/images/icon.png",
     "scheme": "healthapp",
-    "userInterfaceStyle": "automatic",
+    "userInterfaceStyle": "dark",
+    "backgroundColor": "#0d0d0f",
     "ios": {
-      "icon": "./assets/expo.icon"
+      "icon": "./assets/expo.icon",
+      "bundleIdentifier": "xyz.rehbock.health",
+      "supportsTablet": true
     },
     "android": {
+      "package": "xyz.rehbock.health",
       "adaptiveIcon": {
-        "backgroundColor": "#E6F4FE",
+        "backgroundColor": "#0d0d0f",
         "foregroundImage": "./assets/images/android-icon-foreground.png",
         "backgroundImage": "./assets/images/android-icon-background.png",
         "monochromeImage": "./assets/images/android-icon-monochrome.png"
@@ -25,10 +29,11 @@
     },
     "plugins": [
       "expo-router",
+      "expo-secure-store",
       [
         "expo-splash-screen",
         {
-          "backgroundColor": "#208AEF",
+          "backgroundColor": "#0d0d0f",
           "image": "./assets/images/splash-icon.png",
           "imageWidth": 76
         }