[TD-6359]<test>: "add test case for escape '_' by '\' "

[TD-6285]<feature>: added directive for db name in restful interface

[TD-6356]<fix>: Fix the crash in TS-187

'select current_database(); should be select database();' in code comments

* [TD-6247]<fix>: handle JNI_TDengine_ERROR in prepareStmtImp

* modified the networkTimeout test cases

[TD-6312]<test>: last_row query in table with 100 columns

[schemaless][RunCITest]

[TD-6387] To avoid the uncessary check on results

* [TD-6294]<fix>: taosdemo support long arg

fix conflict with develop branch.

* fix few words.

* declare default child tables number.

[ci skip] update cfg key

[TD-6336]<fix> reproduce and fix core

[TD-6343]<fix>: taos crash at tscSubquery.c:2447

[TD-6330]<fix> fix free error

[td-6260]<enhance>: Optimize the client-side query performance

ADD syntax desc

[ci skip]disable crash_gen test

* [TD-5875]<featur>: taosdemo show progress

* empty commit for CI

* better msg for create child table.

* fix total child tables bug.

 To avoid the uncessary check on the number of returned result from virtual nodes.

* [TD-5875]<featur>: taosdemo show progress

* empty commit for CI

* better msg for create child table.

merge from master into develop