docs: seed CHANGELOG.md (Keep-a-Changelog format) (#80)

## Summary
Adds an initial `CHANGELOG.md` in Keep-a-Changelog format. Recent
commits are bucketed into Added/Fixed/Changed/Documentation/CI from
their conventional-commit prefixes.

Closes **Row-2 Phase 3** of the 2026-05-26 estate tech-debt audit chain
for this repo. The audit
([standards#197](hyperpolymath/standards#197))
flagged 180/279 repos missing CHANGELOG (65% gap).

## Adopting auto-regeneration
For ongoing auto-regeneration, adopt the
[`changelog-reusable.yml`](https://github.com/hyperpolymath/standards/blob/main/.github/workflows/changelog-reusable.yml)
workflow
([standards#206](hyperpolymath/standards#206))
in this repo's CI. Uses the canonical
[`templates/cliff.toml`](https://github.com/hyperpolymath/standards/blob/main/templates/cliff.toml).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

CHANGELOG.md

@@ -0,0 +1,74 @@
+<!--
+SPDX-License-Identifier: MPL-2.0
+SPDX-FileCopyrightText: 2026 Jonathan D.A. Jewell (hyperpolymath)
+-->
+
+# Changelog
+
+All notable changes to `reposystem` will be documented in this file.
+
+This file is generated from conventional commits by the
+[`changelog-reusable.yml`](https://github.com/hyperpolymath/standards/blob/main/.github/workflows/changelog-reusable.yml)
+workflow (`hyperpolymath/standards#206`). Adopt the workflow in this repo's CI to keep this file in sync automatically — see
+[`templates/cliff.toml`](https://github.com/hyperpolymath/standards/blob/main/templates/cliff.toml)
+for the canonical config.
+
+The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/);
+this project aims to follow [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+- feat(aggregator): estate organization — manifest, thread runner, generated superproject (#63)
+- feat(repo-batcher): from-scratch verified build-out (#59)
+- feat(bust): extend schema with alert_remediations + seed 11 entries (#15)
+- feat(scaffoldia): add zig-edge template for unified-zig-api stack
+- feat: add rpa-elysium, total-upgrade, and total-recall as submodules
+- feat(scaffoldia): wire RepoKind taxonomy into CLI — new + kinds commands
+- feat(scaffoldia): add boj-cartridge template and fix RepoKind build
+- feat(scaffoldia): add repo-kind taxonomy, trainyard connection graph, and provisioner
+- feat(crg): add crg-grade and crg-badge justfile recipes
+- feat: wire conflow config validation pipeline
+
+### Fixed
+
+- fix(licence): rb56-work — clear scaffold-placeholder leak (superproject) (#64)
+- fix(ci): canonicalise all 12 hypatia-scan.yml (kill templater regeneration drift) (#51)
+- fix(ci): bump a2ml/k9-validate-action pins off broken/stale SHAs (standards#85) (#50)
+- fix(ci): CodeQL language-aware detection (#42)
+- fix(ci): hypatia-scan Comment step must not gate the scan (12 copies) (#41)
+- fix(security): replace placeholder crypto with audited crate implementations (#39)
+- fix(recon-wasm): restore missing builtins.rs (E0583 build blocker) (#40)
+- fix(ci): Phase-2 fleet submission must not fail the security gate (#38)
+- fix(ci): hypatia-scan.yml -- --exit-zero + GITHUB_TOKEN (hyperpolymath/hypatia#213) (#26)
+- fix(ci): rsr-antipattern duplicate heredoc + setup-beam ubuntu24 (#28)
+
+### Documentation
+
+- docs: record tech-debt audit findings (2026-05-26) (#74)
+- docs(repo-batcher): correct status to verified L1–L8 build-out (post #59) (#61)
+- docs(repo-batcher): correct to verified-accurate state (no V ever; Zig stub unimplemented) (#58)
+- docs(repo-batcher): mark V layer legacy/transitional pending Zig port (#57)
+- docs: Item 11 Group A — promote stub .adoc from canonical .md (#47)
+- docs(readme): add SPDX header and standard badges
+- docs(readme): add SPDX header and/or standard badges
+- docs: add per-directory READMEs and fix EXPLAINME file map (CRG D→C)
+- docs(governance): CRG v2.0 STRICT audit — C (declared) -> D (honest)
+- docs: track unresolved mirror and compliance tasks
+
+### CI
+
+- ci(rust): convert rust-ci.yml to thin wrapper (standards#174) (#70)
+- ci(gitignore): ignore generated/* artefacts (Refs standards#93) (#67)
+- ci: redistribute concurrency-cancel guard to read-only check workflows (#60)
+- ci: add templated k9iser-regen trigger (mirrors boj-build.yml) (#52)
+- ci(hypatia): adopt canonical SARIF code-scanning integration + report truth-fix (#49)
+
+## Pre-history
+
+Prior commits to this file's introduction are recorded in git history but not formally classified into Keep-a-Changelog sections. To backfill, run `git cliff -o CHANGELOG.md` locally using the canonical [`cliff.toml`](https://github.com/hyperpolymath/standards/blob/main/templates/cliff.toml) — this is one-shot mechanical work.
+
+---
+
+<!-- This file was seeded by the 2026-05-26 estate tech-debt audit follow-up (Row-2 Phase 3); see [`hyperpolymath/standards/docs/audits/2026-05-26-estate-documentation-debt.md`](https://github.com/hyperpolymath/standards/blob/main/docs/audits/2026-05-26-estate-documentation-debt.md). -->