fix: OPDS browser OOM (#403)

## Summary

- Rewrite OpdsParser to stream parsing instead of full content
- Fix OOM due to big http xml response

Closes #385 

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lib/OpdsParser/OpdsStream.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <Stream.h>
+
+#include "OpdsParser.h"
+
+class OpdsParserStream : public Stream {
+ public:
+  explicit OpdsParserStream(OpdsParser& parser);
+
+  // That functions are not implimented for that stream
+  int available() override;
+  int peek() override;
+  int read() override;
+
+  virtual size_t write(uint8_t c) override;
+  virtual size_t write(const uint8_t* buffer, size_t size) override;
+
+  ~OpdsParserStream() override;
+
+ private:
+  OpdsParser& parser;
+};