[kreczko]

Summary

render/
├── CHANGELOG.md   (new — Keep a Changelog format, calendar-versioned)
└── AGENTS.md       (modified — new "Documentation and Changelog" section)

Part of a workspace-wide rollout (see FAST-HEP/fasthep-dev, task 2026-10-26-package-docs-rollout) giving every FAST-HEP package a real CHANGELOG.md and a stated policy for keeping it current. No docs/ tree exists here yet, so no Sphinx page is added (the AGENTS.md entry says so explicitly).

CHANGELOG.md is backfilled with real content: a ## [2026.08.1] section covering the last tagged release (two months of history, 2026.06.1..2026.08.1), and a populated ## [Unreleased] section covering fixes merged since.

Evidence

Before: no CHANGELOG.md, no stated docs-update policy.
After: content verified by direct inspection against the real git log ranges.

Merge Danger

Documentation-only. No source, test, or dependency changes. Zero behavioural risk.

AI-assisted contributions

This PR's content was generated by Claude (Sonnet 5), orchestrated by @kreczko across a multi-session workspace effort. What was AI-generated: the CHANGELOG.md content (synthesized from git log between tags, grouped into user-facing bullets, categorized per Keep a Changelog), and the AGENTS.md policy section (templated identically across all participating repos). What was reviewed: the repository owner read and approved the diff before pushing (this workspace's standard two-gate review: push, then PR). Known limitation: the CHANGELOG.md backfill is a best-effort reconstruction from commit history, not a release-time verbatim record.

🤖 Generated with Claude Code