Add column information as table header for `flutter emulators` command.
**Before:**
```
2 available emulators:
Pixel_3_API_30 ⢠Pixel 3 API 30 ⢠Google ⢠android
Resizable_API_33 ⢠Resizable API 33 ⢠Google ⢠android
To run an emulator, run 'flutter emulators --launch <emulator id>'.
To create a new emulator, run 'flutter emulators --create [--name xyz]'.
You can find more information on managing emulators at the links below:
https://developer.android.com/studio/run/managing-avdshttps://developer.android.com/studio/command-line/avdmanager
```
**After:**
```
2 available emulators:
Id ⢠Name ⢠Manufacturer ⢠Platform
Pixel_3_API_30 ⢠Pixel 3 API 30 ⢠Google ⢠android
Resizable_API_33 ⢠Resizable API 33 ⢠Google ⢠android
To run an emulator, run 'flutter emulators --launch <emulator id>'.
To create a new emulator, run 'flutter emulators --create [--name xyz]'.
You can find more information on managing emulators at the links below:
https://developer.android.com/studio/run/managing-avdshttps://developer.android.com/studio/command-line/avdmanager
```
fixes#140656