SwaggerEditor@next: consolidate strategy for user accessible default definitions

[tim-lai]

By default, on initial load, if no definition is saved in localStorage, we display AsyncAPI 2.4 Streetlights YAML definition via a SwaggerUI url prop.

Currently, via the Topbar -> Editor menu we offer

• OAS3.0 JSON
• OAS3.1 JSON
• OAS2.0 JSON
• AsyncAPI 2.4 (streetlights) JSON
• AsyncAPI 2.4 Petstore Kafka JSON

Expected Editor menu options:

• Final marketing friendly OAS3.1 YAML definition
• Provide Petstore OAS2.0 YAML definition
• Provide Petstore OAS3.0 YAML definition
• Continue using AsyncAPI's Streetlights definition, but as YAML.
• Approved developer JSON definitions.

Expected keyboard shortcuts:

• Provide keyboard shortcuts to one or more definitions listed above. Currently F6/F7/F8 assigned to OAS 3.1 / AsyncAPI 2.x / OAS 2.0 categories.

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related:

#3264
#3266