Merge pull request 'Add hello world Go program and Makefile' (#3) from implement/hello-world into main

Makefile

@@ -0,0 +1,10 @@
+.PHONY: build run clean
+
+build:
+	go build -o hello main.go
+
+run: build
+	./hello
+
+clean:
+	rm -f hello

go.mod

@@ -1,3 +1,3 @@
 module testbed
 
-go 1.26
+go 1.24

main.go

@@ -0,0 +1,7 @@
+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("Hello, World!")
+}