fix: reduce drop dnode speed to make data more secure

docs(stream)

docs(stream)

fix(tsdb): default value of tsdbPageSize

fix: reset errorcode after check leader

fix: should not fsync in log level is error

enh(stream): forbid source db replica > 1

fix: change err msg while vnode is stoped

fix: incorrect error code for repeated dnode creation

enh: adjust batchSize dynamically on retryBackoff

fix: reduce the frequency of retry in sync not ready case while alter db

fix: remove sch status on timeout

Co-authored-by: Nroot <root@fantastic-pipe-1.localdomain>

refact: post sem in vnode while sync timeout

fix: refact some example files

fix: fix invalid retrieved buffer page causing crash