Fix performance issues in json_dom.cc and improve query optimization

[sjdevgo]

Changes made:

• Fixed performance bottlenecks in the json_dom.cc file by optimizing queries and reducing unnecessary operations.
• Improved memory management in data processing, resulting in better overall efficiency.

Why these changes are important:

These optimizations improve the speed of JSON parsing and processing, which is crucial for larger datasets. The changes were tested on local builds and show significant performance improvements.

Testing:

• Ran unit tests for the modified code.
• Ensured backward compatibility with existing features.

Additional Information:

This change does not affect other parts of the codebase and should not introduce regressions.

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