feat(java,info): add prefix for adj/pg and add datatype parser test

[yangxk1]

Reason for this PR

close #814

What changes are included in this PR?

1. add adjacentList and PropertyGroup default prefix when parsing Yaml
2. add test for date/timestamp datatype Yaml Parser

Are these changes tested?

yes

Are there any user-facing changes?

yes

[codecov-commenter]

Codecov Report

❌ Patch coverage is 83.33333% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 77.22%. Comparing base (23c46c2) to head (ea17afb).

Files with missing lines	Patch %	Lines
...org/apache/graphar/info/yaml/AdjacentListYaml.java	66.66%	0 Missing and 1 partial ⚠️
...rg/apache/graphar/info/yaml/PropertyGroupYaml.java	88.88%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #820      +/-   ##
============================================
+ Coverage     77.18%   77.22%   +0.04%     
- Complexity      607      615       +8     
============================================
  Files            85       84       -1     
  Lines          8858     8866       +8     
  Branches       1043     1047       +4     
============================================
+ Hits           6837     6847      +10     
+ Misses         1781     1779       -2     
  Partials        240      240              

Flag	Coverage Δ
java-info	85.03% <83.33%> (+0.31%)	⬆️

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[yangxk1]

@shivendra-dev54 , thank you again

[Copilot]

Pull request overview

This PR implements default prefix generation for AdjacentList and PropertyGroup when parsing YAML files (addressing issue #814), and adds a test for date/timestamp datatype parsing.

Key changes:

• AdjacentListYaml now generates a default prefix using the adjacency list type name when prefix is null or empty
• PropertyGroupYaml now generates a default prefix by concatenating property names when prefix is null or empty
• New test added to verify date and timestamp data types can be loaded and serialized correctly

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

File	Description
maven-projects/info/src/main/java/org/apache/graphar/info/yaml/PropertyGroupYaml.java	Adds default prefix generation by concatenating property names with underscores
maven-projects/info/src/main/java/org/apache/graphar/info/yaml/AdjacentListYaml.java	Adds default prefix generation using adjacency list type name
maven-projects/info/src/test/java/org/apache/graphar/info/PropertyTest.java	Adds test for date/timestamp datatype YAML parsing and imports required classes

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[shivendra-dev54]

@yangxk1
will this project show up in GSoC ?
what are your thoughts ?

[yangxk1]

@yangxk1 will this project show up in GSoC ? what are your thoughts ?

I think you will be interested in this email https://lists.apache.org/thread/ydzor82fxlpj7v91kln9z4gt5o33p1b2