Pipe: Optimized the key reducer logic & OPC UA sink reuse logic & value + quality in OPC UA tree client-server model

[Caideyipi]

Description

As the title said.

---

This PR has:

• been self-reviewed.
  • concurrent read
  • concurrent write
  • concurrent read and write
• added documentation for new or modified features or behaviors.
• added Javadocs for most classes and all non-trivial methods.
• added or updated version, license, or notice information
• added comments explaining the "why" and the intent of the code wherever would not be obvious
  for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold
  for code coverage.
• added integration tests.
• been tested in a test IoTDB cluster.

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Key changed/added classes (or packages if there are too many classes) in this PR

[codecov]

Codecov Report

❌ Patch coverage is 87.91209% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 39.16%. Comparing base (9386468) to head (921d7a2).
⚠️ Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
...db/db/pipe/sink/protocol/opcua/OpcUaNameSpace.java	78.72%	10 Missing ⚠️
...e/iotdb/db/pipe/sink/protocol/opcua/OpcUaSink.java	96.15%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #16921      +/-   ##
============================================
+ Coverage     39.07%   39.16%   +0.09%     
- Complexity      207      212       +5     
============================================
  Files          5034     5048      +14     
  Lines        334594   334961     +367     
  Branches      42619    42685      +66     
============================================
+ Hits         130750   131195     +445     
+ Misses       203844   203766      -78     

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[sonarqubecloud]

Quality Gate passed

Issues
7 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud