refactor: better model serialization to minimize conversion time

[marius-mather]

Description

Try to map our DB models more directly to the API response schemas - minimize the amount of processing that needs to happen to convert data into a response

Changes

• Map attributes of DB models to response schema fields - so we can return users directly from the database in API responses
• Some more tweaks to user queries

Checklist

• I have commented my code, particularly in hard-to-understand areas
• I have added unit / integration tests that prove my fix is effective or that my feature works
• I have run all tests locally and they pass
• I have updated the documentation (if applicable)
• For any new secrets, I have updated the shared spreadsheet and the GitHub Secrets.

How to Test Manually (if necessary)

Run uv run pytest

[Copilot]

Pull request overview

Refactors admin user serialization to reduce response conversion overhead by mapping SQLModel/SQLAlchemy models directly into Pydantic response schemas via from_attributes.

Changes:

• Enable from_attributes on BiocommonsUserResponse, PlatformMembershipData, and GroupMembershipData so routes can return DB models directly.
• Add computed properties on membership models to supply API-facing fields (platform_name, group_name, group_short_name, updated_by_email).
• Adjust admin user query construction to optionally skip membership eager-loading, and update the count query path.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
routers/admin.py	Switch admin user endpoints to return ORM users directly; add query option to skip eager-loading for count queries; cache allowed-resource subqueries.
db/types.py	Configure membership response models for attribute-based loading; alias updated_by from updated_by_email; enforce timezone awareness for updated_at.
db/models.py	Add computed properties used by attribute-based serialization for membership name fields and updater email.