Adopt the engineering documentation standard

Adopt the engineering documentation standard Declares the repository as kind: library, which is what decides how much it owes. A Composer plugin is consumed rather than run, so it has no environments to describe and no quick start beyond the one already in the README. It owes a documentation index and an architecture page, not four files that would be stubs. The README keeps every word of the customising guide and gains the front matter the standard requires: status, requirements, a quick start, the commands as a table rather than four bash fences, how we work, ownership and distribution. Someone arriving cold can install it and knows who to ask. docs/architecture.md is new and says the thing that was written down nowhere: the presets are the interface, so changing a rule changes the build of every project that installs this plugin, and the .dist overwrite on every composer install is deliberate rather than a bug to work around. CLAUDE.md held a description of the package, which is a fact about the code and belongs where engineers look. It is now the single pointer to AGENTS.md, and AGENTS.md carries the guardrails: the overwrite behaviour, a preset change being a release, and hook installation needing a real checkout because a broken hook fails silently at commit time. Ownership is @hussainweb, the maintainer. Support is a GitHub issue rather than a Slack channel, because this repository is public and people outside Axelerant install the package. No CI workflow. The checks are not wired up here yet; docs-check passes locally at 0 block, 0 warn. Co-Authored-By: Claude Opus 5 (1M context) Claude-Session: https://claude.ai/code/session_01XmzqahsmAXBn5wJab92jP2