feat: Introduce privateData and publicData

[ianshade]

The contributor

This PR is being opened on behalf of TV 2 Norge.

Type of contribution

This is a

• Bug fix
• Feature
• Code improvement
• Documentation improvement
• Other (please specify)

Current behavior

Current behavior is described in the Background section of the RFC #1074, that this PR is a continuation of.

New behavior

On the document interfaces representing Rundown Playlists, Rundowns, Segments, Parts, Pieces, AdLib Pieces and Adlib Actions, the following optional properties are added:

• publicData - the public-facing metadata that has some meaning to the outside world, and the external systems will have access to, through means like the Live Status Gateway's topics
• privateData - data available only to the blueprints, where the blueprints can store any internal information for their own access later, e.g. to be used in methods like executeAction and getEndStateForPart

The metaData property is still available where it was, but marked as deprecated removed.

Note: publicData will be exposed through LSG in a separate PR due to other pending refactoring.

Test instructions

Other information

This change is a feature from the perspective of Blueprints API consumers. From that perspective it's also a breaking change, since the metaData is removed in favor of the newly introduced properties.

Status

• PR is ready to be reviewed
• The functionality has been tested by the author
• Relevant unit tests has been added / updated
• Relevant documentation (code comments, system documentation) has been added / updated

[jstarpl]

With #1070 now merged, is this PR ready to go out of the "Draft" status? We are nearing the end of testing for v1.50, and looking to stabilize v1.51 soon.

[ianshade]

This is now ready for review. I have resolved all the merge conflict up to this point.