Treat a zero payload limit as none when decompressing a stream

set_payload_max_length(0) means no limit, but StreamHandle compared the
decompressed size against 0, so every compressed response read through
the streaming API failed.

httplib.h

@@ -15598,10 +15598,8 @@ inline ssize_t ClientImpl::StreamHandle::read_with_decompression(char *buf,
         [this](const char *data, size_t data_len) {
           decompress_buffer_.append(data, data_len);
           auto limit = body_reader_.payload_max_length;
-          if (decompressed_bytes_read_ + decompress_buffer_.size() > limit) {
-            return false;
-          }
-          return true;
+          return limit == 0 ||
+                 decompressed_bytes_read_ + decompress_buffer_.size() <= limit;
         });
 
     if (!decompress_ok) {

test/test.cc

@@ -22411,6 +22411,17 @@ TEST_F(StreamApiTest, GetWithParams) {
   EXPECT_TRUE(read_body(result).find("foo=bar") != std::string::npos);
 }
 
+#ifdef CPPHTTPLIB_ZLIB_SUPPORT
+TEST_F(StreamApiTest, GetCompressedWithNoPayloadLimit) {
+  httplib::Client cli(HOST, PORT);
+  cli.set_payload_max_length(0);
+  auto result = httplib::stream::Get(cli, "/hello");
+  ASSERT_TRUE(result.is_valid());
+  EXPECT_FALSE(result.get_header_value("Content-Encoding").empty());
+  EXPECT_EQ("Hello World!", read_body(result));
+}
+#endif
+
 TEST_F(StreamApiTest, GetConnectionError) {
   httplib::Client cli(HOST, 9999);
   EXPECT_FALSE(httplib::stream::Get(cli, "/hello").is_valid());