feat(metadata): enhance metadata handling by sanitizing extracted data and updating documentation for file storage

internal/tools/files_test.go

@@ -0,0 +1,28 @@
+package tools
+
+import "testing"
+
+func TestDecodeBase64AcceptsWhitespaceAndMultipleVariants(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{name: "standard with whitespace", input: "aG V s\nbG8=", want: "hello"},
+		{name: "raw standard", input: "aGVsbG8", want: "hello"},
+		{name: "standard url-safe payload", input: "--8=", want: string([]byte{0xfb, 0xef})},
+		{name: "raw url-safe payload", input: "--8", want: string([]byte{0xfb, 0xef})},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			got, err := decodeBase64(tc.input)
+			if err != nil {
+				t.Fatalf("decodeBase64(%q) error = %v", tc.input, err)
+			}
+			if string(got) != tc.want {
+				t.Fatalf("decodeBase64(%q) = %q, want %q", tc.input, string(got), tc.want)
+			}
+		})
+	}
+}