ConstReadonlyAPPEND_THROTTLE_MS: 16rAF-aligned throttle for STROKE_APPEND messages.
ReadonlySNAPSHOT_JITTER_MAX_MS: 250Maximum jitter for late-joiner snapshot responses — small enough that humans don't notice the delay, large enough that two responders are unlikely to collide.
ReadonlySTALE_INPROGRESS_MS: 5000Receivers GC in-progress strokes whose updatedAt is older than this.
Timing constants (milliseconds).