Bring back the Block Exporter and Workspace Factory to the Blockly Developer Tools

[MichaelHinrichs]

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Component

Blockly Developer Tools

Problem

I can see the exporter being a bit redundant when users can copy/past the JavaScript/JSON for their blocks one at a time, but it greatly streamlined the process. And why remove the Workspace Factory?

Request

Bring them back.

Alternatives considered

No response

Additional context

The feature are still in the version of the Blockly Developer Tools that is in the demos of https://github.com/google/blockly.