Waitlist tools on your roster, honest stream status, and cancellation fixes

**Waitlists are now visible and workable everywhere.** Class cards on the
Schedule and Check-in pages show how many people are waiting (for example
"5 waitlist"), and every waitlisted client on a roster has an **Add to class**
button that moves them straight onto the roster — with a clear confirmation if
the class is already full and you want to squeeze them in anyway. You can also
select several waitlisted clients and promote them together; they are added in
queue order and each gets the usual "you're in" message.

**A freed seat now always offers itself to the waitlist.** Removing a client
from a class as staff now promotes the next eligible person on the waitlist,
exactly like it already happened when a member cancelled themselves.

**Members can cancel again.** A recent update accidentally broke online
self-cancellation for regular class bookings ("Could not cancel the booking"
on your website). That is fixed — members can cancel normally again, and a
member who never signed a venue waiver is no longer blocked from *leaving* a
class (signing is still required where it matters: booking and purchasing).

**The Remove from Class dialog now tells the truth.** Instead of "a fee may
apply", it checks your cancellation window and says exactly what will happen —
including a clear note that a staff removal never charges the late fee (use
Mark No-Show if the fee should apply).

**Stream status you can trust.** The "Online ready" pill no longer shows on
classes that are already over, and clicking a pill's health check no longer
flips past classes into a false "Encoder offline" alarm. The health dialog also
no longer closes itself when you click inside it.

**Go Live improvements.** The live page now keeps a "Back to schedule" link
while you are live (leaving the page does not end the broadcast), the duration
counter survives a page refresh and shows the real time since the stream
started, and the preview no longer gets stuck on "Playback unavailable" while
your encoder is connecting — it quietly retries until the picture is up. You
can also **pause a live stream**: viewers see "the instructor paused the
stream" until you resume, and when a stream ends, viewers see that it ended
instead of a frozen player.

**Adding someone to a full class now tells you what happens.** Both routes —
**Add Client** and **Add to class** from the waitlist — ask the same clear
question before they overbook: "18 of 18 places are taken. Adding this client
takes this class to 19. That is 1 over the room's capacity. Everyone already
booked keeps their place." Previously it only said "Class is at capacity.
Override and add anyway?" without telling you the numbers.