Central mapping from error atoms (returned by PhoenixKitStats.Groups and used across its LiveViews) to translated human-readable strings.

Supported reason shapes

• plain atoms — :group_not_found, :port_taken, etc.
• strings — passed through unchanged
• anything else — rendered as "Unexpected error: <inspect>"

Example

iex> PhoenixKitStats.Errors.message(:group_not_found)
"Stats group not found."