feat: configure EC remotely

[Spiral-Memory]

Brief Title

This PR adds a feature to remotely configure EmbeddedChat using the EmbeddedChat RC app.

Acceptance Criteria Fulfillment

• [x] Added all the required string/boolean/select settings in the EmbeddedChat RC app
• [x] Refactored the EmbeddedChat RC app's read setting logic
• [x] Introduced a fetch function to read RC app settings
• [x] Added a useRemoteProps hook that overrides the existing props if any of the props match those in the remote configuration

The implementation is simple: before displaying the EmbeddedChat, we fetch the remote props from EC settings. If a new prop is present or an existing one needs to be overridden, it overrides the prop and then shows the EmbeddedChat component. These overrides happen only when remoteOpt is passed as true.

We can't directly mutate the props, so I have added a state config that now handles the props accordingly.

Fixes #597

Video/Screenshots

https://github.com/RocketChat/EmbeddedChat/assets/78961432/8f2e5027-2a8d-4723-8c2b-33ae7cbf9336

[Spiral-Memory]

Hey @sidmohanty11 ,

This PR is ready for review. It fixes some minor issues and mainly adds a feature to remotely configure the props. I've explained its workings in the PR description. Please take a look.

Thanks!