Preserve file info state across M36 retries

[Old-Ding]

Fixes #1096.\n\nSummary:\n- Preserve the named-file info response state across GetFileInfoResponse retries.\n- Reuse the same GCodeFileInfo and GlobalVariables until the JSON response is emitted, so customInfo collected during chunked parsing is not lost while a print is running.\n\nTesting:\n- git diff --check HEAD~1..HEAD\n- git ls-files --eol src/Platform/RepRap.cpp src/Platform/RepRap.h\n\nNot run: full firmware build, because this local workspace is missing arm-none-eabi-g++, Eclipse headless build, and the required sibling dependencies CANlib/CoreN2G/RRFLibraries.

CI notes

• Current CLAAssistant failure is a contributor license agreement gate.
• This is an account/legal gate, not a code failure in the M36 retry state diff.

[github-actions]

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