Fix EAS local builds and resolve require cycles

- Add dotenv-cli for EAS local builds to load env vars
- Break circular dependencies in store/hooks imports
- Add env var validation with clear error messages
- Remove hardcoded Sentry auth token from sentry.properties
- Add .ipa files to .gitignore

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/mobile/src/lib/authErrorHandler.ts

@@ -1,6 +1,7 @@
 import { router } from "expo-router";
 import { supabase } from "./supabase";
-import { useAuthStore } from "../store";
+// Import directly from authStore to avoid circular dependency with store/index.ts
+import { useAuthStore } from "../store/authStore";
 
 /**
  * Handles authentication errors from edge function calls.