feat(tmq): support show

refactor: vnode

feat: handle null value

fix(shell): memory free error.

fix: allow startup if the log directory does not exist

fix(query): add an null ptr check

enh: add flag in syncEnv, to deal with expired timer

fix(query): fix taosshell crash when arithmetic operation with NULL concstant

fix: set ready status while alterdb

enh(tmq): delayed task

concstant

TD-15132

refactor: return vgroup global verison