chore: format

0.6.38

0.6.39

0.6.40

0.6.41

Introduces SHOW_ACTIVE_USERS_COUNT_ADMIN_ONLY environment variable that,
when enabled, restricts the active user count display to admin users only.

This change provides:
- Privacy: Non-admin users cannot see how many users are active
- Performance: Reduces backend load by preventing API requests from
  non-admin users when the feature is enabled
- Scalability: Significantly reduces /api/usage endpoint calls in
  deployments with hundreds of concurrent users

Changes:
- Backend: Add SHOW_ACTIVE_USERS_COUNT_ADMIN_ONLY env variable in env.py
- Backend: Expose config setting via /api/config endpoint
- Frontend: Check user role and config before displaying active user count
- Frontend: Prevent API calls to /api/usage when user is not authorized

Default behavior: Feature is disabled (false) to maintain backward
compatibility. All users can see active user count unless explicitly
restricted by setting SHOW_ACTIVE_USERS_COUNT_ADMIN_ONLY=true.

Resolves open-webui#13026

Rename environment variable from SHOW_ACTIVE_USERS_COUNT_ADMIN_ONLY to
ENABLE_ACTIVE_USERS_COUNT_ADMIN_ONLY to follow the established naming
convention used throughout the codebase where feature flags start with
ENABLE_.

Changes:
- Backend: Renamed env variable in env.py
- Backend: Updated import and API response key in main.py
- Frontend: Updated config key reference in UserMenu.svelte

The functionality remains the same - when set to true, only admin users
can see the active user count display.

Rename environment variable to ENABLE_PUBLIC_ACTIVE_USERS_COUNT and
reverse the logic for better clarity and consistency with codebase
naming conventions.

Changes:
- Variable: ENABLE_PUBLIC_ACTIVE_USERS_COUNT (default: "True")
- When True (default): Everyone can see active user count (current behavior)
- When False: Only admins can see active user count
- Updated frontend logic to match reversed semantics

This naming better follows the ENABLE_* pattern used throughout the
codebase and makes the purpose more intuitive: "enable public visibility"
is clearer than "enable admin-only restriction".