Two parts:
1. queue.js: websocket events (execution_start / executed / etc.) can
arrive on the websocket transport BEFORE the REST response that
gives us their prompt_id. The previous handlers looked up the pid
in promptIds and bailed when it wasn't found — so the very first
generation in a batch consistently lost its highlight and per-combo
image stamp, and the overlay missed its progress events.
Add a pendingByPid event buffer. When an event arrives for an
unknown pid, queue it. When the patched api.queuePrompt finally
resolves and registers the pid, replay the buffered events for it.
Snapshot _currentBatchComboKey at call time so the queued combo key
stays correct even if the await resolves out of order.
2. generation-data.js: when the overlay opens mid-batch, seed the
progress bar on the currently-running combo's grid cards by
reading _activeBatch.runningPromptId synchronously. Without this,
a late-opened overlay only started showing progress on the *next*
running combo.
Closes#241
Mehdi Chaid
9c927b5011