[#28420] Fix type inference for closures over local variables

[lakshitbahl]

###Description:
This PR resolves closure-related type inference regressions (see #28420) and restores compatibility with Python 3.11+ opcode changes. It introduces two distinct fixes under a unified closure-handling improvement, allowing us to un-skip testLocalClosure.

1. Type-vs-Value Cell Confusion
   Prevents the inference engine from confusing synthetic inferred types with real runtime closure values. Introduces the _TypeInCell marker class to safely wrap, track, and unwrap inferred types within the frame emulation, ensuring strict isolation from actual Python cell contents.

2. Python 3.11+ Shared-Slot Indexing
   Fixes LOAD_CLOSURE and LOAD_DEREF indexing for Python 3.11 and newer. Replaces the legacy arg -= len(co_varnames) arithmetic, which broke when captured parameters shared a slot in the new unified localsplus array with version-aware slot-name resolution. This correctly maps variables and prevents out-of-bounds IndexError exceptions that were previously being swallowed by the safe-mode execution and degraded to Any.

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