chore: rename copier -> cp (#16)

README.md

@@ -29,7 +29,7 @@ go get go-simpler.org/assert
 > [!tip]
 > When developing a library, you may want to keep `go.mod` small (or, even better, empty).
 > In such cases, it is recommended to just copy-paste `assert`, as it is tiny and rarely updated.
-> See the `cmd/copier` helper to do this automatically.
+> See the `cmd/cp` utility to do this automatically.
 
 ## 📋 Usage
 

cmd/copier/main.go → cmd/cp/main.go

@@ -1,9 +1,10 @@
-//go:build copier
+//go:build cp
 
-// Copier is a convenience tool that copies the assertions into a project,
-// so that they can be used without introducing a direct dependency.
+// Cp is a utility to copy [assert] for use without introducing a direct dependency.
 //
-// Usage: //go:generate go run -tags=copier go-simpler.org/assert/cmd/copier@<version> [-dir=<working-directory>]
+// Usage:
+//  1. Add //go:generate go run -tags=cp go-simpler.org/assert/cmd/cp@<version> [-dir=<working-directory>]
+//  2. Run go generate ./...
 package main
 
 import (
@@ -98,7 +99,7 @@ func writeFile(path, content string) error {
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at https://mozilla.org/MPL/2.0/.
 
-// Code generated by go-simpler.org/assert/cmd/copier. DO NOT EDIT.
+// Code generated by go-simpler.org/assert/cmd/cp. DO NOT EDIT.
 
 `
 	return os.WriteFile(path, []byte(header+content), 0644)

embed.go

@@ -1,10 +1,9 @@
-//go:build copier
+//go:build cp
 
 package assert
 
 import _ "embed"
 
-// These files are used by the cmd/copier tool. Ignore them.
 var (
 	//go:embed assert.go
 	MainFile string