feat: add iOS support and harden receipt scanning

.gitignore

@@ -40,3 +40,20 @@ postgres_data/
 
 # remotion render output
 marketing-video/out/
+
+# iOS app — Xcode project is generated from app/ios/project.yml via XcodeGen,
+# never hand-edited or committed (see app/ios/README.md).
+app/ios/*.xcodeproj/
+app/ios/*.xcworkspace/
+app/ios/DerivedData/
+app/ios/.build/
+app/ios/**/xcuserdata/
+
+# local Codex/MCP workspace metadata
+/.agents/
+/.mcp.json
+
+# local diagnostic artifacts
+/auth-db-run4-meta.txt
+/build_err.txt
+/test-reactbits-bg.html