Function updateKeyValue

updateKeyValue(namespace, key, value): Promise<any>
Creates or updates a key-value pair in persistent storage.

Stores a value under the specified key within the given namespace. If the key already exists, its value will be overwritten. Supports primitive types with automatic string conversion for API compatibility.
Parameters
- namespace: string
  Namespace for organizing related key-value pairs
- key: string
  Unique identifier within the namespace
- value: string | number | boolean
  Value to store (primitive types supported)
Returns Promise<any>
Promise resolving to the stored value
Throws
When update request fails or service returns non-200 status

Example: Store Configuration Setting
```
await updateKeyValue('device-config', 'maxRetries', 5);
await updateKeyValue('user-prefs', 'darkMode', true);
await updateKeyValue('app-state', 'lastLogin', '2024-01-15');
```