[WIP] Fix FcbReference balancing on file open/close

[Copilot]

• Analyze codebase and understand the FcbReference imbalance bug
• Review PR Rebase MCB commits onto udf-dev base to show only MCB changes #3 (assorted/reactos) for write.cpp resource locking changes
• Fix double FcbReference increment in create.cpp (remove extra increment in UDFCompleteFcbOpen and _SEH2_FINALLY)
• Fix extra VcbReference increment in create.cpp (remove line 2078)
• Fix missing FcbReference decrement in main close path in close.cpp
• Fix DASD close path to use UDFDecrementReferenceCounts
• Apply write.cpp resource locking fix from PR Rebase MCB commits onto udf-dev base to show only MCB changes #3 (FcbPagingIoResource)
• Run code review and security checks

Original prompt

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This section details on the original issue you should resolve

<issue_title>Could what a developer just told me be causing the same issue that was fixed by a different PR?</issue_title>
<issue_description>"When I added LCB it uncovered an old hidden bug with FcbReference balancing on file open/close. Increments outnumber decrements, so files sometimes don't get released — leads to all kinds of fun stuff like concurrent access errors and unmount issues. Been on it for over a week and want to finish it off."

The PR that might be related to that statement is assorted#3.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Could what a developer just told me be causing the same issue that was fixed by a different PR? #106

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