Builder - Add sap.cloud section in generateLibraryManifest

Is your feature request related to a problem? Please describe.

I cannot use the generateLibraryManifest task to generate manifests for UI5 libraries deployed to SCP Cloud Foundry Portal, because the mandatory section sap.cloud is not supported.

Describe the solution you'd like

I believe adding 2 new optional fields to the .library file, and mapping them to the sap.cloud section would be ideal.

Describe alternatives you've considered

Generating the manifest.json in a build, copying it from dist and manually adding the sap.cloud section.

Additional context

I'm using Builder for a UI5 library deployed to SCP Cloud Foundry Portal (managed Approuter).

The applications and libraries must be deployed to a html5-apps-repo service instance with the sap.cloud.service field present in their manifest.json.

From SAP Help Portal - Expose HTML5 Applications in Portal:

To expose an HTML5 Application in SAP Cloud Platform Portal , you need to add some information to the manifest.json file.

Configuration	Mandatory?	Description
sap.cloud.service	Mandatory	Defines the business service.
semanticObject and action	Mandatory	Defines the navigation intent, which is composed of a semantic object and the action that is performed on this object.

Obs: Although this is not documented, I've found that UI5 libraries don't need the semanticObject and action (it wouldn't make sense anyway).

This is what this section looks like:

"sap.cloud": {
  "public": true,
  "service": "my.example.service"
}

This is the current generated manifest.json in file manifestCreator.js:

	return {
		"_version": descriptorVersion.toString(),
		"sap.app": await createSapApp(),
		"sap.ui": createSapUi(),
		"sap.ui5": createSapUI5(),
		"sap.fiori": createSapFiori(),
		"sap.platform.abap": createSapPlatformABAP(),
		"sap.platform.hcp": createSapPlatformHCP()
	};