Show time zone on availability display

Requested by: Rachel Petersen, Escalon

When viewing candidate/client availability in the Live Stage Tracker - for example: Matchmaker, there's no visible label indicating what time zone the displayed times are in. Times are already auto-converted to the viewer's local time zone, but this isn't communicated in the UI, so it's easy to second-guess. Add a time zone label near the availability display for clarity.