docs: Add v0.10.4 release documentation

[Copilot]

Prepares v0.10.4 release documentation with deep code analysis of 4 PRs merged after v0.10.3.

Release Theme

Infrastructure improvements and Go 1.26 compatibility. No breaking changes.

Documentation Deliverables

• GITHUB_RELEASE_NOTES.md - Concise format matching v0.10.3 style for GitHub release page
• RELEASE_NOTES_v0.10.4.md - Simplified release notes following v0.10.2 format with:
  • Summary and impact for each PR
  • Categorized under "Chore"
  • Full changelog link
• RELEASE_README.md - Usage guide with PR summary and dependencies comparison tables
• SUMMARY.md - Executive summary of analysis methodology and key findings

PRs Analyzed

PR	Category	Key Change
#1477	Chore	Go 1.26 support via dependency updates
#1476	Chore	Release automation scripts with dry-run mode
#1475	Chore	Repo consolidation: develop→main, cmd/hz integration
#1478	Chore	Final release preparation

Critical Dependency Updates

sonic v1.14.0 → v1.15.0

• Go 1.26 compatibility
• JSON encoding optimizations
• Better panic traces with JSON context

netpoll v0.7.0 → v0.7.2

• MallocAck memory management fixes
• Zero-copy code cleanup

User Impact

Primary benefit: Go 1.26 compatibility. Secondary: JSON performance improvements, enhanced developer tooling. Backward compatible.

Original prompt

准备发布v0.10.4，给v0.10.3后每个pr进行清晰的总结（需要深入到代码），然后按之前release log 分类进行输出

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[AsterDY]

@copilot RELEASE_NOTES_v0.10.4.md 给一个精简版本，只保留 summary和impact。格式按照 https://github.com/cloudwego/hertz/releases/tag/v0.10.2 分类

[Copilot]

@copilot RELEASE_NOTES_v0.10.4.md 给一个精简版本，只保留 summary和impact。格式按照 https://github.com/cloudwego/hertz/releases/tag/v0.10.2 分类

Simplified RELEASE_NOTES_v0.10.4.md to keep only summary and impact, following v0.10.2 format. Commit: f5b8ca5