add hosting support for Flutter web apps

### Is this feature request related to a new or existing Amplify category?

hosting

### Is this related to another service?

_No response_

### Describe the feature you'd like to request

Add project configuration support for [Flutter web distributions](https://docs.flutter.dev/get-started/web#build) to allow for static web hosting. This will likely require two additional fields in the project configuration:

- `Web Distribution Directory` (`Distribution Directory Path` for JavaScript apps)
- `Web Build Command` (`Build Command` for JavaScript apps)

Currently folks developing Flutter apps for web can workaround the lack of support by changing their project configuration to JavaScript:

```
Project information
| Name: myflutterapp
| Environment: dev
| Default editor: Visual Studio Code
| App type: javascript
| Javascript framework: none
| Source Directory Path: lib
| Distribution Directory Path: build/web
| Build Command: flutter build web
| Start Command: flutter run -d chrome
```

The two important fields here are:

```
| Distribution Directory Path: build/web
| Build Command: flutter build web
```

With this workaround Flutter developers are able to run `amplify publish` to upload their web output

### Describe the solution you'd like

flutter web hosting

### Describe alternatives you've considered

switching project config to JavaScript

### Additional context

_No response_

### Is this something that you'd be interested in working on?

- [ ] 👋 I may be able to implement this feature request

### Would this feature include a breaking change?

- [ ] ⚠️ This feature might incur a breaking change