Fetch notifications using the current server time

[grantfitzsimmons]

Fixes #4566

This change fixes an issue where users in timezones with an offset larger than one set for Django (by default, America/Chicago) would not receive new notifications due to the fetching logic using the date of the user's browser locale and not the server time (which is used when creating new notification_message records), resulting in them not being fetched.

This PR adds a new API endpoint to fetch the current server time and integrates it into the notifications polling mechanism to ensure consistent time-based queries.

• Adds Django view and URL pattern to expose /context/server_time.json
• Introduces fetchServerTime utility to retrieve and parse server time
• Updates useNotificationsFetch to use server time in its polling URL

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Since I see you requested a self-review, @melton-jason: please feel free to edit this PR however you see fit!

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Checklist

• Self-review the PR after opening it to make sure the changes look good and
  self-explanatory (or properly documented)
• Add relevant issue to release milestone
• Add relevant documentation (Tester - Dev)
• Add automated tests

Testing instructions

Test the behavior in this PR against the latest tagged release:

• Use a browser extension to set your timezone to be something in the future relative to where you are (using a browser extension like https://change-timezone.pdfwork.com/ (for testing, I used the Pacific/Apia locale which has an offset of 780 , which is the time zone difference from UTC (in minutes) (with daylight consideration))
• Open the query builder and run a query. After it has been run, click "Export to CSV"
  • In v7 with a time zone set far in the future, you should not receive any notification even after Specify fetches new notifications. When you reload the page, the new notification would be visible then.
  • In issue-4566-time, you should receive a notification once the browser sends a request to fetch notifications. You should be able to either wait for a notification to appear or click on the "Notifications" navigation menu item.

[emenslin]

• Use a browser extension to set your timezone to be something in the future relative to where you are (using a browser extension like https://change-timezone.pdfwork.com/ (for testing, I used the Pacific/Apia locale which has an offset of 780 , which is the time zone difference from UTC (in minutes) (with daylight consideration))
• Open the query builder and run a query. After it has been run, click "Export to CSV"
  • In v7 with a time zone set far in the future, you should not receive any notification even after Specify fetches new notifications. When you reload the page, the new notification would be visible then.
  • In issue-4566-time, you should receive a notification once the browser sends a request to fetch notifications. You should be able to either wait for a notification to appear or click on the "Notifications" navigation menu item.

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Looks good, I receive the notifications instantly on the issue branch!

[lexiclevenger]

• Use a browser extension to set your timezone to be something in the future relative to where you are (using a browser extension like https://change-timezone.pdfwork.com/ (for testing, I used the Pacific/Apia locale which has an offset of 780 , which is the time zone difference from UTC (in minutes) (with daylight consideration))
• Open the query builder and run a query. After it has been run, click "Export to CSV"
  • In v7 with a time zone set far in the future, you should not receive any notification even after Specify fetches new notifications. When you reload the page, the new notification would be visible then.
  • In issue-4566-time, you should receive a notification once the browser sends a request to fetch notifications. You should be able to either wait for a notification to appear or click on the "Notifications" navigation menu item.

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Looks good! I received the notification without needing to refresh.

[bhumikaguptaa]

• Use a browser extension to set your timezone to be something in the future relative to where you are (using a browser extension like https://change-timezone.pdfwork.com/ (for testing, I used the Pacific/Apia locale which has an offset of 780 , which is the time zone difference from UTC (in minutes) (with daylight consideration))
• Open the query builder and run a query. After it has been run, click "Export to CSV"
  • In v7 with a time zone set far in the future, you should not receive any notification even after Specify fetches new notifications. When you reload the page, the new notification would be visible then.
  • In issue-4566-time, you should receive a notification once the browser sends a request to fetch notifications. You should be able to either wait for a notification to appear or click on the "Notifications" navigation menu item.

Works as expected!