feat: Read and write LedgerCache to file (#2761)

Fixes #2413.

src/data/impl/InputFile.cpp

@@ -0,0 +1,58 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2025, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#include "data/impl/InputFile.hpp"
+
+#include <xrpl/basics/base_uint.h>
+
+#include <cstddef>
+#include <cstring>
+#include <ios>
+#include <iosfwd>
+#include <string>
+#include <utility>
+
+namespace data::impl {
+
+InputFile::InputFile(std::string const& path) : file_(path, std::ios::binary | std::ios::in)
+{
+}
+
+bool
+InputFile::isOpen() const
+{
+    return file_.is_open();
+}
+
+bool
+InputFile::readRaw(char* data, size_t size)
+{
+    file_.read(data, size);
+    shasum_.update(data, size);
+    return not file_.fail();
+}
+
+ripple::uint256
+InputFile::hash() const
+{
+    auto sum = shasum_;
+    return std::move(sum).finalize();
+}
+
+}  // namespace data::impl