chore: initialize Expo SDK 55 project with TypeScript

React Native + Expo Router setup with strict TypeScript,
path aliases, and dark-first configuration.

tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "extends": "expo/tsconfig.base",
+  "compilerOptions": {
+    "strict": true,
+    "ignoreDeprecations": "6.0",
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["src/*"]
+    }
+  }
+}