feat: optimize insert in java sdk

[dl239]

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

• What is the current behavior? (You can also link to an open issue here)

• What is the new behavior (if this is a feature change)?

[codecov]

Codecov Report

Attention: 151 lines in your changes are missing coverage. Please review.

Comparison is base (9401a5e) 75.35% compared to head (8f6213b) 75.39%.

Files	Patch %	Lines
...openmldb/sdk/impl/InsertPreparedStatementImpl.java	62.91%	49 Missing and 7 partials ⚠️
src/sdk/sql_cluster_router.cc	0.00%	45 Missing ⚠️
...openmldb/sdk/impl/InsertPreparedStatementMeta.java	78.64%	16 Missing and 6 partials ⚠️
...om/_4paradigm/openmldb/jdbc/SQLInsertMetaData.java	60.00%	4 Missing and 2 partials ⚠️
.../main/java/com/_4paradigm/openmldb/sdk/Common.java	0.00%	6 Missing ⚠️
...penmldb/sdk/impl/InsertPreparedStatementCache.java	84.61%	4 Missing and 2 partials ⚠️
...paradigm/openmldb/sdk/impl/SqlClusterExecutor.java	66.66%	5 Missing and 1 partial ⚠️
...digm/openmldb/common/codec/FlexibleRowBuilder.java	0.00%	1 Missing and 1 partial ⚠️
.../java/com/_4paradigm/openmldb/sdk/QueryFuture.java	0.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #3525      +/-   ##
============================================
+ Coverage     75.35%   75.39%   +0.03%     
- Complexity      587      634      +47     
============================================
  Files           717      719       +2     
  Lines        129893   130000     +107     
  Branches       1280     1315      +35     
============================================
+ Hits          97886    98011     +125     
+ Misses        31737    31714      -23     
- Partials        270      275       +5     

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