docs(samples): add API reference and Kitchen Sink for Presence

[sreenara]

COMPLETES #SPARK-492000

This pull request addresses

1. webex.github.io/webex-js-sdk/ main page should now feature a Presence link as well. There should also be an API reference link for the Presence API so developers can refer to this.
2. Presence kitchen sink page should allow a developer to input an access token like the remaining pages and initialize the plugin
3. Once the plugin is initialized, a developer should be able to do these functions:
   • Subscribe to another user's presence and receive updates. Updates can be displayed in a text box
   • Set presence for the user

by making the following changes

• Created a new page in the docs/samples folder for presence which fulfills the requirements for the Jira.
• Added typedoc package to @webex/plugin-presence and modified tsconfig.json to generate the API reference documents for presence.

Change Type

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [x] Documentation update
• [ ] Tooling change
• [ ] Internal code refactor

The following scenarios were tested

1. Initialize webex token in the new page
2. Get presence status for the user that's logged in
3. Get presence status for another user
4. Set presence for the user that's logged in
5. Subscribe to presence notifications from another user
6. Unsubscribe from presence notifications from another user
7. Check the API reference for Presence and ensure the details mentioned are correct

API Reference walkthrough: https://github.com/webex/webex-js-sdk/assets/131740035/a17bf88e-236d-4e9c-9735-128614b21b2b

Kitchen sink walkthrough: https://github.com/webex/webex-js-sdk/assets/131740035/c724c5e8-250d-46fe-acd9-0fcce144be1c - Part 1 https://github.com/webex/webex-js-sdk/assets/131740035/135dc844-bc12-4d0a-8943-b30ed1828074 - Part 2

Setting presence status for self: https://github.com/webex/webex-js-sdk/assets/131740035/09b2d238-189d-4ac7-8ea4-eef8fa4a8d02

I certified that

• [x] I have read and followed contributing guidelines

• [x] I discussed changes with code owners prior to submitting this pull request

• [x] I have not skipped any automated checks

• [x] All existing and new tests passed

• [x] I have updated the documentation accordingly

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