fix: add input validation to search_by_id method

[aeromomo]

• Add null/empty ID validation to prevent crashes
• Handle invalid ID conversion gracefully (ValueError, OverflowError)
• Return empty SearchResult for invalid inputs instead of raising exceptions
• Improve robustness for edge cases like None, empty strings, invalid formats

This prevents potential crashes when search_by_id is called with malformed or invalid ID values, making the search API more robust.

Description

Related Issue

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Performance improvement
• Test update

Changes Made

Testing

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have tested this on the following platforms:
  • Linux
  • macOS
  • Windows

Checklist

• My code follows the project's coding style
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published

Screenshots (if applicable)

Additional Notes

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