Feature/55712 file attachment input

[sushmi21]

This PR adds the File attachment input.

• You should be able to drag and drop the files and attach it.
• You should be able to click attach button and browse for files to attach
• If multiple files are added, you should be able to horizontally scroll them. (Scroll bar appears only on hover)
• Please also try to attach a file with the large name. There are no max-width applied for the file preview chips now. Please let me know if we need to enforce a max-width.
• Please check Figma prototypes
• Please also check the failing file upload scenario. No prototype provided for this. We could show the file name in red or show 'Failed Upload' as in version 2 (current implementation in this PR). Please let me know your opinion.

To test, please use configure a file storage provider in your endpoint editor or use this endpoint: https://endpoint-dev.cognigy.ai/36d5dfe244e2bf217d61a7c381b16c16ab25f0aac9a748351937d8ab9aa46452. If you get CORS error, please run cognigy-ai in the cluster and import this package. Create a flow and add this flow to the exported endpoint. And then use the endpoint url in webchat
Endpoint-Web_2024-01-22_13-31-31.zip

[dshire]

The code changes look good to me. I noticed 2 things we need to change:

1. The file preview bubble looks stylistically too different from the others, need rework
2. If I upload files with a message and send, I only see the message, not the file upload preview

Both need to be changed in chat-components repo I guess? How do you want to tackle this, maybe an immediate follow-up?

[sushmi21]

The code changes look good to me. I noticed 2 things we need to change:

1. The file preview bubble looks stylistically too different from the others, need rework
2. If I upload files with a message and send, I only see the message, not the file upload preview

Both need to be changed in chat-components repo I guess? How do you want to tackle this, maybe an immediate follow-up?

Yes, the file output has to be handled separately and in the chat components repo. This PR is just about File inputs.

[dshire]

chat-components fixes will follow-up