test: add comprehensive test suite for logging, request ID, and user management

Signed-off-by: Noooste <83548733+Noooste@users.noreply.github.com>

backend/pkg/logger/redact_test.go

@@ -0,0 +1,32 @@
+package logger
+
+import "testing"
+
+func TestRedactKey(t *testing.T) {
+	cases := []struct {
+		name string
+		in   string
+		want string
+	}{
+		{"empty", "", "***"},
+		{"short", "abc", "***"},
+		{"just-under-threshold", "abcdefghijk", "***"},   // 11 chars
+		{"at-threshold", "abcdefghijkl", "abcd…ijkl"},     // 12 chars
+		{"long", "GK5a9bfcdefghijklzW9q", "GK5a…zW9q"},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := RedactKey(tc.in); got != tc.want {
+				t.Errorf("RedactKey(%q) = %q, want %q", tc.in, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestRedactToken_AlwaysStars(t *testing.T) {
+	for _, in := range []string{"", "abc", "very-long-secret-token-value"} {
+		if got := RedactToken(in); got != "***" {
+			t.Errorf("RedactToken(%q) = %q, want ***", in, got)
+		}
+	}
+}