History writes deliberately give up after a bounded 250 ms wait so they
never stall ComfyUI; the existing bounded-timeout test still proves that.
The concurrent replay tests assert that every peer succeeds, which is a
serialization and first-capture property, so they now raise the budget
to the shared 30 s busy timeout while the first writer is held open.
The budget is one named constant, EXECUTION_BUSY_TIMEOUT_MS, shared by
the transaction helper and the background writer.
Before: 20/20 'database is locked' with the held writer. After: 0/20.
Vito Sansevero
94d50d15f2