fix: update the logic for maxFiles count in upload docs step

[shubhamv-ss]

Description

In this PR, I've made following changes.

1. Disable Upload Feature on Limit: When the maxFiles limit is reached, disable the upload feature to prevent users from uploading more files.
2. Dynamic maxFiles Count: Make the maxFiles count dynamic based on the number of already uploaded documents.
3. Display error message: You can only upload up to 3 files.

Why

maxFiles hardcoded value, causing following issues:

1. Exceeding maxFiles limit: Users can upload multiple files even if maxFiles is set to 3.
2. No error on exceeding limit: Attempting to upload a 4th file when maxFiles is 3 fails without displaying an error.
3. Page refresh bypass: Refreshing the page resets the maxFiles limit, allowing users to upload more than 3 files.
4. Delete all uploaded files: Users can delete all uploaded files, even if the total number exceeds the maxFiles limit.

Issue

#233

Checklist

• I have performed a self-review of my own code
• I have successfully tested my changes locally

[oyo]

lgtm

[lavanya-bmw]

please update changelog

[shubhamv-ss]

please update changelog

Hi @lavanya-bmw , I updated the changelog file.
Let me know if it's in correct format.

[oyo]

lgtm

[lavanya-bmw]

lgtm

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud