feat: add LuaRocks rockspec for pandoc-a2ml

Enables installation via `luarocks install pandoc-a2ml` once published.
Packages the reader, writer, and filter as Lua modules.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

pandoc-a2ml-scm-1.rockspec

@@ -0,0 +1,53 @@
+-- SPDX-License-Identifier: MIT
+-- (PMPL-1.0-or-later preferred; MIT required for LuaRocks OSI-approved policy)
+--
+-- pandoc-a2ml-scm-1.rockspec — LuaRocks package spec for pandoc-a2ml.
+--
+-- Provides Pandoc reader, writer, and filter for A2ML (Attested Markup Language).
+
+rockspec_format = "3.0"
+package = "pandoc-a2ml"
+version = "scm-1"
+
+source = {
+   url = "git://github.com/hyperpolymath/pandoc-a2ml.git",
+   branch = "main",
+}
+
+description = {
+   summary = "Pandoc reader, writer, and filter for A2ML (Attested Markup Language)",
+   detailed = [[
+      pandoc-a2ml provides a custom Pandoc reader, writer, and filter for the
+      A2ML (Attested Markup Language) format. A2ML is an attestation-native
+      markup language designed for documents that carry trust metadata,
+      cryptographic signatures, and provenance information.
+
+      Features:
+        - Custom reader: parse .a2ml files into the Pandoc AST
+        - Custom writer: render Pandoc AST back to .a2ml format
+        - Filter: transform attestation directives within Pandoc pipelines
+        - Preserves headings, directive blocks, inline formatting, and lists
+   ]],
+   homepage = "https://github.com/hyperpolymath/pandoc-a2ml",
+   license = "MIT",
+   maintainer = "Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>",
+   labels = { "pandoc", "a2ml", "markup", "filter", "reader", "writer", "attestation" },
+}
+
+dependencies = {
+   "lua >= 5.1",
+}
+
+build = {
+   type = "builtin",
+   modules = {
+      ["pandoc-a2ml"]          = "a2ml.lua",
+      ["pandoc-a2ml.reader"]   = "a2ml-reader.lua",
+      ["pandoc-a2ml.writer"]   = "a2ml-writer.lua",
+      ["pandoc-a2ml.filter"]   = "a2ml-filter.lua",
+   },
+   copy_directories = {
+      "docs",
+      "examples",
+   },
+}