fix: msg compatibility

fix(tmq): handle adding subtable for subscribing stb

enh: refact sync callback func

fix: remove last stt load info resetting from fs iterator

fix: fsync wal files and meta if data size not synced yet beyond a threshold

doc: update show variables

fix: wrong cpu usage

fix: invalid read problem of tsdb path

refactor: add some logs.

enh: refact syncMsg code

refactor(stream): fill history

* fix: taosbenchmark query concurrent segfault

update taos-tools 719fc88

* fix: taosbenchmark free null child tbl name

test: adjust unstable case

fix(query): leastsquares handles unsigned types

enh(query): improve the aggregate performance.

fix: drop index error