feat: solve day 5 part 1

cmd/05/main_test.go

@@ -0,0 +1,27 @@
+package main_test
+
+import (
+	"testing"
+
+	solution "github.com/StevanFreeborn/advent-of-code-2025/cmd/05"
+)
+
+func TestSolvePartOneWithExampleInput(t *testing.T) {
+	expected := 3
+
+	result := solution.SolvePartOne("EXAMPLE.txt")
+
+	if result != expected {
+		t.Errorf("SolvePartOne with example input: expected %d, got %d", expected, result)
+	}
+}
+
+func TestSolvePartOneWithInput(t *testing.T) {
+	expected := 643
+
+	result := solution.SolvePartOne("INPUT.txt")
+
+	if result != expected {
+		t.Errorf("SolvePartOne with input: expected %d, got %d", expected, result)
+	}
+}