docs: add CLI doc

[vagetablechicken]

close #2941

[codecov]

Codecov Report

Patch coverage has no change and project coverage change: +0.01 🎉

Comparison is base (242ad02) 75.69% compared to head (215cb42) 75.70%.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #3105      +/-   ##
============================================
+ Coverage     75.69%   75.70%   +0.01%     
  Complexity      393      393              
============================================
  Files           666      672       +6     
  Lines        124760   124871     +111     
  Branches       1113     1117       +4     
============================================
+ Hits          94439    94539     +100     
- Misses        30085    30096      +11     
  Partials        236      236              

Impacted Files	Coverage Δ
src/cmd/sql_cmd.h	25.92% <ø> (ø)
src/catalog/client_manager.h	29.06% <0.00%> (-1.17%)	⬇️
src/rpc/rpc_client.h	74.15% <0.00%> (-1.13%)	⬇️
src/sdk/db_sdk.cc	67.84% <0.00%> (-0.67%)	⬇️
src/catalog/client_manager.cc	43.05% <0.00%> (-0.29%)	⬇️
src/client/tablet_client.cc	58.77% <0.00%> (-0.23%)	⬇️
src/storage/mem_table.cc	89.13% <0.00%> (-0.15%)	⬇️
src/sdk/sql_cluster_router.cc	61.83% <0.00%> (-0.15%)	⬇️
...ava/com/_4paradigm/openmldb/jdbc/SQLResultSet.java	14.38% <0.00%> (-0.06%)	⬇️
src/client/taskmanager_client.cc	0.00% <0.00%> (ø)
... and 29 more

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[github-actions]

SDK Test Report

  92 files    92 suites   1m 59s ⏱️
185 tests 175 ✔️ 10 💤 0 ❌
231 runs  221 ✔️ 10 💤 0 ❌

Results for commit 215cb42.

♻️ This comment has been updated with latest results.

[github-actions]

Linux Test Report

590 tests   582 ✔️  26m 46s ⏱️
  58 suites      7 💤
  52 files        1 ❌

For more details on these failures, see this check.

Results for commit 215cb42.

♻️ This comment has been updated with latest results.