mainframe-removal

Apply the transformations from a transformation guide to convert mainframe-specific COBOL to standard COBOL. **Prerequisite**: A transformation guide must exist (see `cobol-mainframe-planning` skill). ## Transformation Requirements ### Data Operations - Replace each CICS/VSAM construct with its standard COBOL equivalent per the plan - Add FILE STATUS checks after EVERY file operation: - Check for success (00) before proceeding - Handle "not found" (23) distinctly from I/O errors (3x) - Handle "file not exists" (35) at OPEN time - Add explicit CLOSE statements in all code paths (including error paths) ### UI/Terminal Operations (BMS maps, SEND/RECEIVE) - Replace with simple stubs or ACCEPT/DISPLAY statements - Do NOT spend time replicating screen layouts - Focus on preserving data flow, not UI fidelity ### Error Handling - Replace CICS RESP/RESP2 checks with equivalent FILE STATUS logic - Replace HANDLE CONDITION with explicit status checking after operations - Ensure error paths don't leave files open See [references/cics-transformation-examples.md](references/cics-transformation-examples.md) for before/after code examples. ## Verification After transformation: - Code MUST compile without errors - Test with valid input → should execute core business logic - Test with missing/invalid files → should fail gracefully, not crash ## Preserve - All original business logic - Data transformations and calculations - Validation rules ## Checklist - [ ] All EXEC CICS commands replaced - [ ] FILE STATUS declared for all files - [ ] FILE STATUS checked after every I/O operation - [ ] CLOSE statements in all code paths - [ ] Code compiles successfully - [ ] Basic test execution passes