docs(ios): add debugging guide and fix stale web/ios paths

[ashleeradka]

Summary

• Adds a Debugging section to apps/ios/README.md covering Safari Web Inspector (for the WKWebView — JS / CSS / network / console.log) and the Xcode debugger (for native Swift code), with common recipes for plugin, streaming, and load-failure debugging.
• Fixes three stale web/ios/... path references left over from the relocation to apps/ios/ (feat(ios): relocate Capacitor iOS shell as apps/ios peer (LUM-1544) #31302):
  • apps/ios/.gitignore — drops reference to a build-ios-slot.yaml workflow that no longer exists; updates web/ios/README.md → apps/ios/README.md.
  • apps/web/src/runtime/native-auth.ts — updates the plugin file path in the doc comment.
  • apps/web/src/runtime/native-biometric.ts — updates the plugin file path in the doc comment.

Why these specifics

• Safari Web Inspector vs Xcode console: a frequent debugging trip-up is console.log from the web side not showing up in the Xcode console — it goes to Safari Web Inspector only. The README now calls this out explicitly.
• Capacitor 6+ behaviour: Web Inspector works on Debug builds because Capacitor auto-enables WKWebView.isInspectable; Release / TestFlight builds are intentionally not inspectable. Linked to the upstream Capacitor docs.
• Common recipes: covers the three failure modes most likely to land on iOS-shell debugging — a native plugin not responding (Swift breakpoint), an SSE / streaming regression (filter for text/event-stream in Network), and a blank-green-screen WebView load failure (Xcode console for the navigation error).

Test plan

• Read through the new Debugging section in apps/ios/README.md and confirm the Safari steps match current macOS (Settings → Advanced → "Show features for web developers").
• Confirm Safari → Develop menu lists the simulator and the app's bundle ID entry when an App Dev Debug build is running.
• grep -rn "web/ios" apps/ .github/ returns no matches.

🤖 Generated with Claude Code

[devin-ai-integration]

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