WIP channel config extension

[dsrw]

WHY are these changes introduced?

Fixes #0000

WHAT is this pull request doing?

How to test your changes?

Post-release steps

Measuring impact

How do we know this change was effective? Please choose one:

• n/a - this doesn't need measurement, e.g. a linting rule or a bug-fix
• Existing analytics will cater for this addition
• PR includes analytics changes to measure impact

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes

[github-actions]

Unused exports (2)

Filename	exports
packages/app/src/cli/models/extensions/specifications/function.ts	default
packages/app/src/cli/models/extensions/specifications/channel_config_app_extension.ts	ChannelConfigSpecIdentifier

[github-actions]

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