packaging: build recipes for arch, gentoo, nix, void, fedora

Five distro recipes in packaging/, all following the same recipe:
unpack the Gitea release archive (which extracts to fastwc/), run
autoreconf -fi (the generated configure/Makefile.in are not committed),
configure, make, make install - the binary needs only glibc.

Each recipe notes the release prerequisite: the archive URL requires a
v0.1.0 tag on the remote, and Arch/Nix/Void carry an integrity
placeholder to fill in once the tag exists. The PKGBUILD was validated
with makepkg --printsrcinfo, and the full build recipe was run
end-to-end from a Gitea-layout tarball (autoreconf, configure, make,
make install DESTDIR) producing a working /usr/bin/fastwc.

packaging/arch/PKGBUILD

@@ -0,0 +1,27 @@
+# Maintainer: huntedbytheirs <[email protected]>
+pkgname=fastwc
+pkgver=0.1.0
+pkgrel=1
+pkgdesc="A wc replacement that beats GNU wc - SIMD kernels, mmap, threads"
+arch=('x86_64')
+url="https://git.spectoria.dev/huntedbytheirs/fastwc"
+license=('MIT')
+depends=('glibc')
+makedepends=('autoconf' 'automake' 'libtool')
+# requires a v0.1.0 tag on the Gitea remote; replace SKIP with the real
+# sha256sum once the tag exists (makepkg prints it on the first failed build)
+source=("$pkgname-$pkgver.tar.gz::https://git.spectoria.dev/huntedbytheirs/fastwc/archive/v$pkgver.tar.gz")
+sha256sums=('SKIP')
+
+build() {
+    # Gitea archives extract to a directory named after the repo
+    cd "$pkgname"
+    autoreconf -fi
+    ./configure --prefix=/usr
+    make
+}
+
+package() {
+    cd "$pkgname"
+    make DESTDIR="$pkgdir" install
+}