Improve OpenAPI (REST) documentation for the website with a docusaurus plugin

[Sziszka90]

Describe your change

Integrated Redocusaurus to render the App Directory OpenAPI documentation:

Issue: #1001

• Added the redocusaurus preset to website/docusaurus.config.js and website/package.json to render OpenAPI specs with Redoc.
• Added Redoc links to website/sidebars.json and the versioned sidebars (website/versioned_sidebars/version-2.0-sidebars.json, version-2.1-sidebars.json, version-2.2-sidebars.json) so the App Directory API reference is reachable from site navigation.
• Replaced pathname schema links in website/docs/app-directory/spec.md and website/versioned_docs/version-*/app-directory/spec.md to point at the new Redoc routes.
• Removed the obsolete generated app-directory.html files under website/static/schemas/2.0, 2.1, 2.2, and next, which are superseded by the Redoc-rendered docs.
• Updated CHANGELOG.md under Unreleased > Added.

Contributor License Agreement

• I acknowledge that a contributor license agreement is required and that I have one in place or will seek to put one in place ASAP.

Review Checklist

npm run build
cd website; npm run start

• Issue: If a change was made to the FDC3 Standard, was an issue linked above?
• CHANGELOG: Is a CHANGELOG.md entry included?
• API changes: Does this PR include changes to any of the FDC3 APIs (DesktopAgent, Channel, PrivateChannel, Listener, Bridging)?
  • Docs & Sources: If yes, were both documentation (/docs) and sources updated?
  • Conformance tests: If yes, are conformance test definitions (/toolbox/fdc3-conformance) still correct and complete?
  • Schemas: If yes, were changes applied to the Bridging and FDC3 for Web protocol schemas?
    • If yes, was code generation (npm run build) run and the results checked in?
• Context types: Were new Context type schemas created or modified in this PR?
  • Were the field type conventions adhered to?
  • Was the BaseContext schema applied via allOf (as it is in existing types)?
  • Was a title and description provided for all properties defined in the schema?
  • Was at least one example provided?
  • Was code generation (npm run build) run and the results checked in?
• Intents: Were new Intents created in this PR?
  • Were the intent name prefixes and other naming conventions adhered to?
  • Was the new intent added to the list in the Intents Overview?

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[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: Sziszka90 / name: Szilard Ferencz (c466456)

[kriswest]

Thank you for taking this one on.

I'm having trouble with version selection. Its rendering the next version for me instead of 2.2 when thats selected in teh version.menu top right:

then when the next version is selected it switches to 2.2 when you navigate to it. Hence, this needds a nother look (+conflicts resolving)

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.48%. Comparing base (71e1b59) to head (87d370f).
⚠️ Report is 27 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2001   +/-   ##
=======================================
  Coverage   95.48%   95.48%           
=======================================
  Files          85       85           
  Lines        6705     6705           
  Branches      873      939   +66     
=======================================
  Hits         6402     6402           
  Misses        303      303           

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[Sziszka90]

Thank you for taking this one on.

I'm having trouble with version selection. Its rendering the next version for me instead of 2.2 when thats selected in teh version.menu top right:

then when the next version is selected it switches to 2.2 when you navigate to it. Hence, this needds a nother look (+conflicts resolving)

@kriswest Should work now. Can you please retry?