makefile installs zsh completions on macos

Makefile

@@ -1,3 +1,20 @@
-install:
-	go build -o changelog && mv changelog "${HOME}/.local/bin/changelog";
+all: binary shell-completions
+
+
+binary: build-binary install-binary
+
+build-binary:
+	go build -o changelog
+
+install-binary:
+	cp changelog "${HOME}/.local/bin/changelog"
+
+
+shell-completions: generate-shell-completions install-shell-completions
+
+install-shell-completions:
+	cp ./completions/changelog.zsh /usr/local/share/zsh/site-functions/_changelog
+
+generate-shell-completions:
+	./scripts/generate-completions