relative imports

[alecsavvy]

Summary

Briefly describe what this PR does and why.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code generation update (XSD → proto → Go)
• Test improvements
• Performance optimization

Related Issues

Fixes #(issue number)
Related to #(issue number)

Changes Made

• Added/modified XSD schemas
• Updated proto generation tools
• Modified generated protobuf files
• Added/updated Go code
• Updated documentation
• Added/modified tests

DDEX Compliance

• Changes maintain DDEX standard compliance
• XML roundtrip integrity preserved (XML → Proto → XML)
• Field completeness validated (all XSD fields mapped)
• Official DDEX samples still parse correctly
• No breaking changes to public API

Testing

• Added tests for new functionality
• All existing tests pass (make test)
• Comprehensive tests pass (make test-comprehensive)
• Benchmarks show acceptable performance (make benchmark)
• Generated code is up to date (make generate)

Test Results

# Paste relevant test output here
$ make test
✓ All tests passed

$ make test-comprehensive
✓ Conformance tests: X/X passed
✓ Roundtrip tests: X/X passed
✓ Field completeness: 100%

Performance Impact

• No performance impact
• Performance improved
• Performance regression (explain why acceptable)

Benchmark Results (if applicable)

# Before
BenchmarkERN/Parse-8    1000    1234567 ns/op    123456 B/op    1234 allocs/op

# After
BenchmarkERN/Parse-8    1000    1234567 ns/op    123456 B/op    1234 allocs/op

Documentation

• README updated (if applicable)
• CONTRIBUTING.md updated (if applicable)
• TESTING.md updated (if applicable)
• Tool documentation updated (if applicable)
• Code comments added for new public functions

Breaking Changes

If this introduces breaking changes, describe:

1. What breaks
2. How users should migrate
3. Why the breaking change is necessary

Generated Code

• This PR includes generated code changes
• Generated code was created using make generate
• Both source changes and generated output are included

Additional Notes

Any additional information, context, or screenshots that would help reviewers understand this PR.

Checklist

• My code follows the project's style guidelines
• 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
• 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
• Any dependent changes have been merged and published