docs: delete useless and duplicate errorcode page

docs: correct a few typos and improper description

docs: hightlight R language

docs: refine configuration page and delete duplicate client configura…

* [TD-14555]<impr>: remove plugins/mqtt

* [TD-14540]<impr>: taosdump code cleanup

* update taos-tools

* refine 5-taos-tools/taosdump/taosdumpTestInspect.py

* [TD-14540]<impr>: refine tools/taosdumpTest2.py

* remove a few unused checks

* update taos-tools

* debug tools/taosdumpTest2.py

* add more debug

* merge with develop

* remove all MQTT code

* remove all MQTT code

* remove debug from tests/pytest/tools/taosdumpTest2.py

* fix mac compile error

* remove mqttDebugFlag

* enh: remove mqtt plugin

remove mqtt from CMakelists.txt

[TD-14555]

docs: add introduction to schemaless protocols

* docs:doc-cn Node.js add RESTful docs

* docs:doc-cn add Node.js RESTful docs

* docs:docs-cn fix C# invalid hyperlink

* docs:docs-cn node add restful docs fix format

* docs:docs-cn node add restful docs fix with comment

docs: refactor connect page

[TD-14360]

feat(query): group by multi columns

fix(shell): print taos_connect failed reason befor exiting

* [TD-13063]<fix>: Fix win test error.

* fix: resolve win test error.

docs: fix error in escape instructions

docs: remove duplicate file

docs: refine a series of documents

fix(shell): print taos_connect failed reason befor exiting

docs: fix incorrect text and punctuation

docs: fix build error caused by angle bracket