Start a new time record for an employee. If the employee already has an active record of a different type (e.g. switching from work to break), the existing record is automatically clocked out first. Use type "switch" to replace the current work record (e.g. changing customer/project) — this auto-clocks out the existing record and creates a new "work" record. Returns 409 if the employee already has an active record of the same type. Returns 400 if the company requires a customer or project and neither is provided. Returns 400 if the specified customer or project is disabled. Returns 400 if job geofencing applies but start_coordinates is missing or invalid, or if coordinates are outside the allowed perimeter. Returns 429 if a concurrent clock-in is already being processed for this employee. The auto clock-out expiration is set based on the company's daily cut-off time. Also emits the same live admin websocket update as internal clock-in.