new: add just-hook for a hook

test/just-hook-1.0.PKGBUILD

@@ -0,0 +1,26 @@
+pkgname="just-hook"
+pkgver="1.0"
+homepage="https://gitea.phywyj.dynv6.net"
+pkgdesc="Just a Hook file"
+license=("GPL")
+sourses=()
+urls=()
+md5sums=()
+
+src_prepare() {
+  cat > test.HOOK << "EOF"
+target=(/usr/*)
+triggers=("install" "remove")
+operation() {
+  echo "This is a hook."
+}
+EOF
+}
+
+src_build() {
+  :
+}
+
+src_install() {
+  leaf_install_hook test.HOOK
+}