complete codex docs

docs/modules/user_admin.md

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+# User Admin
+
+## Purpose
+
+User, role, and group administration.
+
+## Current Status
+
+- Production
+
+## Dependencies
+
+- auth system
+- role and group tables
+
+## Database Tables
+
+- `users`
+- `user_groups`
+- `user_role_info`
+- `user_group_info`
+
+## Agent Interaction
+
+- none directly
+
+## User Workflow
+
+- account management
+
+## Admin Workflow
+
+- create/edit users
+- manage groups and roles
+- set page limits and email preferences
+
+## Security Concerns
+
+- password handling
+- email uniqueness
+- group permissions
+
+## Known Issues
+
+- older role/group model
+
+## Missing Functionality
+
+- more explicit per-feature permissions
+
+## Suggested Future Improvements
+
+- tie roles into server content, scheduler, files, and billing more clearly
+
+## Recommendation
+
+- Keep / Improve
+