Add tests for auth, rate limiting, security, and util

internal/security/password_test.go

@@ -0,0 +1,22 @@
+package security
+
+import "testing"
+
+func TestHashAndCheckPassword(t *testing.T) {
+	pw := "correct horse battery staple"
+
+	hash, err := HashPassword(pw)
+	if err != nil {
+		t.Fatalf("HashPassword returned error: %v", err)
+	}
+	if hash == "" {
+		t.Fatalf("expected non-empty hash")
+	}
+
+	if !CheckPassword(pw, hash) {
+		t.Fatalf("expected CheckPassword to succeed for correct password")
+	}
+	if CheckPassword("wrong", hash) {
+		t.Fatalf("expected CheckPassword to fail for wrong password")
+	}
+}