feat: modified date range selection to flexible 6 months.

[ganesh-nithin]

Why this change is required

Currently the start date range is calculated based on today's date. It's restricting users to get old data, so this PR aims to change the start date range calculation based on the end date.

Describe your changes

• Changed the start date range calculation from today's date to end date.

How this change has been tested

Tested by loading previous months data.

• User can select at most 190 days date range of data at any in the start & end date interval.

Reference

Checklist

• I have performed a self review of my code and intend to submit as such
• I have added necessary explanations and inline comments for review
• I have considered updating necessary README or other documentations
• I have added/modified necessary automated tests
• This includes a breaking changes and needs to be listed in release notes

[ganesh-nithin]

Client CI is blocked by 3 low severity vulnerabilities (GHSA-pxg6-pf52-xh8x) occurred in devDependency MSW (https://github.com/mswjs/msw). They have an active PR to mitigate the issue mswjs/msw#2312.