Add onboarding, auth flow, design system and project structure

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,25 @@
+# Exclude from repo
+rosetta-android/
+sprints/
+CLAUDE.md
+
+# Xcode
+build/
+DerivedData/
+*.xcuserstate
+*.xccheckout
+*.moved-aside
+*.hmap
+*.ipa
+*.dSYM.zip
+*.dSYM
+
+# Swift Package Manager
+.build/
+Packages/
+Package.resolved
+
+# macOS
+.DS_Store
+*.swp
+*~