lmcp: Arch PKGBUILD + CI job publishing to both aarch64 and x86_64

lmcp is arch=any (pure Lua). One build on the aarch64 runner serves
all pacman targets — the pure-Lua package drops into both repo dbs.

Depends on lua + lua-socket from the target distro's base repos.

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

arch/lmcp/PKGBUILD

@@ -0,0 +1,23 @@
+# Maintainer: Markus Fritsche <mfritsche@reauktion.de>
+# Lightweight MCP server in pure Lua.
+# Source of truth: git.reauktion.de/marfrit/lmcp
+
+pkgname=lmcp
+pkgver=0.3.0
+pkgrel=1
+pkgdesc="Lightweight MCP (Model Context Protocol) server in pure Lua"
+arch=('any')
+url="https://git.reauktion.de/marfrit/lmcp"
+license=('MIT')
+depends=('lua' 'lua-socket')
+source=("${pkgname}-${pkgver}.tar.gz::https://git.reauktion.de/marfrit/lmcp/archive/v${pkgver}.tar.gz")
+sha256sums=('80a37fc41633ae285b86f2f6cdd97f0c922c03022dce09addd47aeb379f2bcff')
+
+package() {
+    cd "${pkgname}"
+    install -Dm644 lmcp.lua           "${pkgdir}/usr/share/lua/5.4/lmcp.lua"
+    install -Dm644 json.lua           "${pkgdir}/usr/share/lua/5.4/json.lua"
+    install -Dm644 server.lua         "${pkgdir}/usr/share/lua/5.4/server.lua"
+    install -Dm755 example_server.lua "${pkgdir}/usr/bin/lmcp-example"
+    install -Dm644 README.md          "${pkgdir}/usr/share/doc/${pkgname}/README.md"
+}