Create more FDC3 developer tools

[kriswest]

FDC3 Workbench has been a great help for developers getting started with FDC3 and developing their first app integrations
See:

• https://github.com/finos/FDC3/blob/main/toolbox/fdc3-workbench/README.md
• https://fdc3.finos.org/toolbox/fdc3-workbench/ (needs to be run inside a desktop agent)

However, it takes up a lot of the screen - hence there is scope for FDC3 developer tools with other form factors, e.g. Widgets that can:

• Display context received on a channel
• Broadcast context on a channel on a button push
• Raise an intent on a button push
• Integrate with test frameworks to send or receive context or intents as part of a test
• etc.

Such tools can be implemented as:

• a standalone web project and later may be contributed to the FDC3 repo (toolbox folder)
• a refactor and update of the existing FDC3 workbench project to create a responsive version (make it bigger to set-up context, make it smaller and it turns into a widget)
• or a combination (e.g. work with the FDC3 workbench in other ways: Workbench sets local storage with defined context examples, if hosted on the same domain widgets can read and use these context examples.