Change the error message on providing task updates when update is given before 6:00AM IST

Issue Description

When a task update is given before 6:00AM IST, it gives the message like Task progress for the day has already been created
The error message should guide the user about the specific time after which update can be given

For example I tried giving update on 13th dec at 5:45AM IST which was not already present and got the error.

Expected Behavior

An error message which guides the user to give the update after 6:00AM IST

Current Behavior

An error like Task progress for the day has already been created

Reproducibility

• This issue is reproducible
• This issue is not reproducible

Steps to Reproduce

1. Try giving a task update before 6:00AM when the previous date update was already given

Severity/Priority

• Critical
• High
• Medium
• Low

Checklist

• I have read and followed the project's code of conduct.
• I have searched for similar issues before creating this one.
• I have provided all the necessary information to understand and reproduce the issue.
• I am willing to contribute to the resolution of this issue.

Thank you for contributing to our project! We appreciate your help in improving it.

Search the backend for the current "Task progress for the day has already been created" message and identify the task-update entry point. Reproduce an update before 6:00AM IST, then adjust the error wording so it tells users to submit after 6:00AM IST. Confirm the existing update behavior remains unchanged.