Add make install: copies compiled binary to ~/bin

Makefile

@@ -1,4 +1,4 @@
-.PHONY: test lint fmt fmt-check check build build-bin dev clean docker hooks
+.PHONY: test lint fmt fmt-check check build build-bin install dev clean docker hooks
 
 # Use `timeout` (GNU coreutils) when available so `make test` is hard-capped.
 # On macOS without coreutils this is empty and the cap is skipped.
@@ -29,6 +29,11 @@ build:
 build-bin:
 	nix-shell -p bun --run "bun build bin/quak.ts --compile --outfile bin/quak"
 
+install: build-bin
+	mkdir -p ~/bin
+	cp bin/quak ~/bin/quak
+	chmod +x ~/bin/quak
+
 dev:
 	@$(YARN) tsc --watch