[bitcoin/bitcoin] ZMQ: add options to configure outbound message high water mark, aka SNDHWM (#14060)

mruddy commented on this pull request.

> @@ -443,11 +443,19 @@ void SetupServerArgs()
gArgs.AddArg(«-zmqpubhashtx=

«, «Enable publish hash transaction in

«, false, OptionsCategory::ZMQ);
gArgs.AddArg(«-zmqpubrawblock=

«, «Enable publish raw block in

«, false, OptionsCategory::ZMQ);
gArgs.AddArg(«-zmqpubrawtx=

«, «Enable publish raw transaction in

«, false, OptionsCategory::ZMQ);
+ gArgs.AddArg(«-zmqpubhashblockhwm=«, strprintf(«Set publish hash block outbound message high water mark (default: %d)», DEFAULT_ZMQ_SNDHWM), false, OptionsCategory::ZMQ);
+ gArgs.AddArg(«-zmqpubhashtxhwm=«, strprintf(«Set publish hash transaction outbound message high water mark (default: %d)», DEFAULT_ZMQ_SNDHWM), false, OptionsCategory::ZMQ);
+ gArgs.AddArg(«-zmqpubrawblockhwm=«, strprintf(«Set publish raw block outbound message high water mark (default: %d)», DEFAULT_ZMQ_SNDHWM), false, OptionsCategory::ZMQ);
+ gArgs.AddArg(«-zmqpubrawtxhwm=«, strprintf(«Set publish raw transaction outbound message high water mark (default: %d)», DEFAULT_ZMQ_SNDHWM), false, OptionsCategory::ZMQ);

there is still a big potential message size difference between just hash and raw{block,tx} so i think having them separate still is better. it just gives people the most flexibility. btw, thanks for the review!