fix: add NSMicrophoneUsageDescription to app.json in LLM example app (#511)

## Description

Fixes an issue where pressing microphone button in voice chat in example
LLM app would crash the app on the IOS devices.

### Introduces a breaking change?

- [ ] Yes
- [x] No

### Type of change

- [x] Bug fix (change which fixes an issue)
- [ ] New feature (change which adds functionality)
- [ ] Documentation update (improves or adds clarity to existing
documentation)
- [ ] Other (chores, tests, code style improvements etc.)

### Tested on

- [ ] iOS
- [ ] Android

### Testing instructions

<!-- Provide step-by-step instructions on how to test your changes.
Include setup details if necessary. -->

### Screenshots

<!-- Add screenshots here, if applicable -->

### Related issues

#510 

### Checklist

- [ ] I have performed a self-review of my code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have updated the documentation accordingly
- [ ] My changes generate no new warnings

### Additional notes

<!-- Include any additional information, assumptions, or context that
reviewers might need to understand this PR. -->

Author: mlodyjesienin

apps/llm/app.json

@@ -33,7 +33,10 @@
     },
     "ios": {
       "supportsTablet": true,
-      "bundleIdentifier": "com.anonymous.llm"
+      "bundleIdentifier": "com.anonymous.llm",
+      "infoPlist": {
+        "NSMicrophoneUsageDescription": "This app needs access to your microphone to record audio."
+      }
     },
     "android": {
       "adaptiveIcon": {

apps/llm/ios/llm/Info.plist

@@ -49,6 +49,8 @@
 	<string>The app needs to access your calendar.</string>
 	<key>NSCalendarsUsageDescription</key>
 	<string>The app needs to access your calendar.</string>
+	<key>NSMicrophoneUsageDescription</key>
+	<string>This app needs access to your microphone to record audio.</string>
 	<key>NSRemindersFullAccessUsageDescription</key>
 	<string>Allow $(PRODUCT_NAME) to access your reminders</string>
 	<key>NSRemindersUsageDescription</key>