Add expression-based field access for CodeMatch and CodeInstruction

[Copilot]

• Understand issue Add expression based CodeMatch.LoadField/StoreField #756: Add expression-based CodeMatch.LoadsField() and CodeMatch.StoresField() methods
• Analyze existing code structure
• Add GetFieldInfo<T> and GetFieldInfo(LambdaExpression) methods to SymbolExtensions class
• Add expression-based LoadsField<T> and StoresField<T> overloads to CodeMatch class
• Add expression-based LoadField<T> and StoreField<T> overloads to CodeInstruction class
• Consolidate CodeInstruction.LoadField/StoreField to follow DRY principles:
  • Added LoadField(FieldInfo, bool) and StoreField(FieldInfo) base overloads
  • Type/string and expression overloads now delegate to base overloads
• Add tests for all new methods (13 tests added)
• Run tests to verify implementation (all pass)
• Run dotnet format to fix formatting
• Run code review (no issues)
• Run CodeQL security check (no issues)

Original prompt

Can you implement #756

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[pardeike]

@copilot Can you doublecheck if we created code that already exists or that can be consolidated? We need to adhere to DRY principles.

[Copilot]

@copilot Can you doublecheck if we created code that already exists or that can be consolidated? We need to adhere to DRY principles.

Reviewed and consolidated CodeInstruction.LoadField/StoreField to follow DRY principles. The opcode selection logic was duplicated across Type/string and expression overloads.

Added new FieldInfo-based overloads (LoadField(FieldInfo, bool) and StoreField(FieldInfo)) that contain the core logic, and refactored existing overloads to delegate to these base methods. This also provides a useful new API surface for users who already have a FieldInfo. (a298a11)