Add LSG support for templateAdLibs

[scriptorian]

This PR has been opened by SuperFly.tv on behalf of EVS Broadcast Equipment.

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

Feature

What is the current behaviour? (You can also link to an open issue here)

LSG offers adLibActions and rundownBaselineAdLibActions in the adLib topic Each adLibAction optionally includes an editableFields property to offer a schema for the adLibOptions property in the REST API for executeAdLib

What is the new behaviour (if this is a feature change)?

A new type of adLibAction has been added to the adLib topic - exposed as an (optional) additional array of templateAdLibs. The templateAdLibActions are intended for actions where important data required to complete the action is not available during getRundown/getSegment processing, for example to support playing a video clip that is stored on an external asset management system. To support this change and to allow robust parameter validation the editableFields property has been renamed optionsSchema and this has been tested to support the important difference between ingest created adlibs where for example a video clip is defined and shouldn't be changeable and 'ad-hoc' adlibs where the video clip information must be provided through the executeAdLib adlibOptions properties.

Other information:

Status

• [x] PR is ready to be reviewed.
• [x] Code documentation for the relevant parts in the code have been added/updated by the PR author
• [x] Relevant unit tests have been checked.
• [x] The functionality has been tested by the PR author

Affected Areas

• This PR affects the Live Status Gateway.
• TemplateAdLibs and the optionsSchema property will not appear unless blueprints create them.