feat: add EAS build config and app store asset structure (FRE-4572)

- Create eas.json with development, preview, and production build profiles
- Add submit configuration for iOS App Store and Google Play
- Create app store metadata with listing copy, keywords, and requirements
- Add screenshot capture guides for iOS and Android
- Add marketing asset directory structure

packages/mobile/eas.json

@@ -0,0 +1,58 @@
+{
+  "cli": {
+    "version": ">= 10.0.0",
+    "appVersionSource": "remote"
+  },
+  "build": {
+    "development": {
+      "developmentClient": true,
+      "distribution": "internal",
+      "ios": {
+        "resourceClass": "m1-medium"
+      },
+      "android": {
+        "buildType": "apk"
+      },
+      "env": {
+        "NODE_ENV": "development"
+      }
+    },
+    "preview": {
+      "distribution": "internal",
+      "ios": {
+        "simulator": true,
+        "resourceClass": "m1-medium"
+      },
+      "android": {
+        "buildType": "apk"
+      },
+      "env": {
+        "NODE_ENV": "development"
+      }
+    },
+    "production": {
+      "ios": {
+        "resourceClass": "m1-medium"
+      },
+      "android": {
+        "buildType": "app-bundle"
+      },
+      "env": {
+        "NODE_ENV": "production"
+      }
+    }
+  },
+  "submit": {
+    "production": {
+      "ios": {
+        "ascAppId": "shieldai-app-id",
+        "appleId": "apple@frenocorp.com",
+        "appleTeamId": "FRENOCORP-TEAM-ID"
+      },
+      "android": {
+        "serviceAccountKeyPath": "./google-play-service-account.json",
+        "track": "internal"
+      }
+    }
+  }
+}