added startedOn and lastReviewedOn

[jeevansegu]

This PR resolves issue #836.
This pull request adds two new fields to the ambassador schema to enable tracking the date an ambassador started and the last time their status was reviewed. This will ensure compliance with the requirement to review ambassador statuses annually.

1. Schema Updates:

   • Added startedOn (Date): Tracks the date an individual became an ambassador.
   • Added lastReviewedOn (Date): Tracks the date the ambassador status was last reviewed.

2. Data Population:

   • Populated startedOn for existing ambassadors based on available historical data.

Data Updates

• Retrieved start dates from existing records, verified by historical Slack messages (populated using the month and year when the ambassador was added to the channel).
• Populated the startedOn field for all current ambassadors.

Code Changes

• Updated the ambassador model to include the new fields.
• Made startedOn date a required field.

Verification

• Start dates were confirmed via Slack server history.

Checklist

• Schema updated with startedOn and lastReviewedOn fields.
• Existing data populated with verified startedOn dates.
• All changes included in a single PR.
• Tested and verified changes.

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@Relequestual : Please review the proposed schema changes and confirm that the populated data aligns with expectations. Any feedback or further suggestions are welcome!

[Relequestual]

Nice work. Thank you for your contribution.

Thank you for the good write up also!

If you want to continue to contribute to the JSON Schema project, I invite you to join our slack server. You can find the link on our website =]

[jeevansegu]

Nice work. Thank you for your contribution.

Thank you for the good write up also!

If you want to continue to contribute to the JSON Schema project, I invite you to join our slack server. You can find the link on our website =]

Thank you =] i will join the server