Add README, runbook, per-script docs, CHANGELOG and LICENSE.

Documents the organise-isos and generate-ventoy-json workflow end-to-end:
quick start in the README, full procedure with troubleshooting and recovery
in docs/RUNBOOK.md, and reference docs for each script covering parameters,
parsing rules, category groupings, and extensibility. Ships a YOLO licence
(no warranty) and seeds CHANGELOG.md for the v0.1.0 release.

CHANGELOG.md

@@ -0,0 +1,28 @@
+# Changelog
+
+All notable changes to this project are documented in this file.
+
+The format is loosely based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
+
+## [0.1.0] - 2026-05-21
+
+First tagged release. Bundles the existing scripts with a documentation set.
+
+### Added
+- `organise-isos.ps1` — filename-driven sorter that moves ISOs into
+  `iso-library/<os>/<version>/<arch>/`. Covers Windows, RHEL family, Fedora
+  family, SUSE, Debian/Ubuntu and derivatives, Arch family, Gentoo, Slackware,
+  independent Linux distros, hypervisors, BSDs, Solaris/illumos, exotic OSes,
+  and rescue tools.
+- `generate-ventoy-json.ps1` — generates a categorised `ventoy.json` menu
+  from the sorted tree, with curated display names and per-family submenus.
+- `README.md` — project overview and quick start.
+- `docs/RUNBOOK.md` — end-to-end build/refresh procedure with troubleshooting
+  and recovery sections.
+- `docs/organise-isos.md` — parameter reference, parsing rules, extensibility
+  guide.
+- `docs/generate-ventoy-json.md` — parameter reference, category groupings,
+  menu output shape.
+- `docs/directory-layout.md` — on-disk structure for the local working copy
+  and the Ventoy USB.
+- `LICENSE` — YOLO licence, no warranty.