Add email option to members identities filter list

[peoray]

Changes proposed ✍️

What

Fixes #703

🤖 Generated by Copilot at 57c829d

This pull request adds email filtering and searching to the member module in the frontend. It updates the identities filter config and the placeholder text of the main filter in frontend/src/modules/member/config/filters. ​

🤖 Generated by Copilot at 57c829d

Search by name or email A new filter option Spring cleaning the frontend

Why

How

🤖 Generated by Copilot at 57c829d

• Add a new option to filter members by email address in the identities filter (link)
• Update the placeholder text of the member search filter to include email (link)

Checklist ✅

• [ ] Label appropriately with Feature, Improvement, or Bug.
• [ ] Add screehshots to the PR description for relevant FE changes
• [ ] New backend functionality has been unit-tested.
• [ ] API documentation has been updated (if necessary) (see docs on API documentation).
• [ ] Quality standards are met.