docs(rest-api): add pin, save & interacted endpoints (ENG-38785) - #488

Running Vale across on the following files affected by this PR:

- articles/error-guide.mdx
- rest-api/conversations/list-global-pinned-conversations.mdx
- rest-api/conversations/pin-group-conversation.mdx
- rest-api/conversations/pin-user-conversation.mdx
- rest-api/conversations/replace-global-pinned-conversations.mdx
- rest-api/conversations/unpin-group-conversation.mdx
- rest-api/conversations/unpin-user-conversation.mdx
- rest-api/messages/mark-message-as-interacted.mdx
- rest-api/messages/pin-message.mdx
- rest-api/messages/save-message.mdx
- rest-api/messages/unpin-message.mdx
- rest-api/messages/unsave-message.mdx

Attempting to initialize Vale linter...
No customer vale configuration detected. Using Mintlify's default configuration.
Attempting to run Vale spellcheck...
Vale spellcheck completed successfully.

articles/error-guide.mdx:
	- 10:57     Did you really mean 'appId'?
	- 11:59     Did you really mean 'appId'?
	- 14:143    Did you really mean 'authOnly'?
	- 19:60     Did you really mean 'api'?
	- 20:118    Did you really mean 'param'?
	- 43:156    Did you really mean 'pasword'?
	- 54:77     Did you really mean 'unban'?
	- 58:78     Did you really mean 'unban'?
	- 84:64     Did you really mean 'customData'?
	- 109:76    Did you really mean 'param'?
	- 119:60    Did you really mean 'iniator'?
	- 143:56    Did you really mean 'updation'?


Found 12 suggested changes across 1 files in 935.78ms