Fix pointer arithmetic for all pointer types

[jserv]

This commit resolves the long-standing limitation where non-char pointer differences didn't work correctly. The root cause was incorrect ARM instruction encoding for arithmetic right shift, not a parser issue.

The fix enables proper pointer differences for all types:

• Integer pointers (int*)
• Struct pointers
• Typedef pointers
• Complex pointer expressions

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Summary by cubic

Fixes pointer arithmetic across all pointer types by correcting ARM SRA encoding and unifying pointer arithmetic in the parser. Pointer differences now return element counts for int*, struct*, typedef pointers, and complex expressions.

• Bug Fixes
  • Corrected ARM arithmetic right shift (register-based) instruction encoding.
  • Unified pointer arithmetic: detects pointer–pointer difference, scales by element size, and preserves pointer type metadata.
  • Expanded tests to cover int/char/struct/typedef pointers, negative and zero differences, array indexing, and complex expressions.

[cubic-dev-ai]

No issues found across 3 files