Add ios nsuserdefaults set command

[panguin6010]

This PR adds a new command to set values in iOS NSUserDefaults, complementing the existing get command.

Features

• Set string, integer, float, and boolean values in NSUserDefaults
• Automatic type detection based on input
• Optional --type flag for explicit type specification
• Changes persist across app restarts via synchronize()

Usage

ios nsuserdefaults set <key> <value> [--type string|int|float|bool]```

## Examples

```bash
ios nsuserdefaults set username "john.doe"
ios nsuserdefaults set isEnabled true
ios nsuserdefaults set maxRetries 5
ios nsuserdefaults set apiVersion 2.5 --type float

Changes

• TypeScript Agent: Implemented set() function with type-specific setters (setBool_forKey_, setInteger_forKey_, setDouble_forKey_, setObject_forKey_)
• TypeScript Agent: Fixed get() to use standardUserDefaults() for consistency with set()
• RPC Layer: Added iosNsuserDefaultsSet export
• Python Command: Added set() command with argument parsing and intelligent type detection
• Tests: Added 6 new test cases covering all value types and error scenarios
• Documentation: Added help file with usage examples

Testing

All tests pass:

python -m unittest tests.commands.ios.test_nsuserdefaults -v