Prepare for release v4.3.0

[ggoranov-smar]

Release v4.3.0

Closes out the changelog for the v4.3.0 release. Branched from clean mainline per RELEASE.md.

No version file to bump — the package version is derived from the git tag at build time via hatch-vcs.

Changed files

• CHANGELOG.md — inserted ## [4.3.0] - 2026-07-20 header below the permanent Unreleased placeholder

Changelog (4.3.0)

Added

• Add case for a template resource_type in append_data method in PaginatedChildrenResult model
• Add Proof model and ProofType enum
• Add a proof field to the Row model
• Add serialization tests for the new model

Next steps (per RELEASE.md, done by a human)

• CI passes on this PR
• Merge to mainline
• Draft & publish GitHub Release, tag v4.3.0 (Create new tag on publish), generate release notes → sets version & triggers PyPI publish

🤖 Generated with Claude Code

[coveralls]

Coverage Report for CI Build 29727074760

Warning

No base build found for commit 89b443d on mainline.
Coverage changes can't be calculated without a base build.
If a base build is processing, this comment will update automatically when it completes.

Coverage: 77.908%

Details

• Patch coverage: No coverable lines changed in this PR.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

Requires a base build to compare against. How to fix this →

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Coverage Stats

Relevant Lines:	10963
Covered Lines:	8541
Line Coverage:	77.91%
Coverage Strength:	3.9 hits per line

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💛 - Coveralls