delete ~1100 redundant parse-only tests from compile.test.ts (#72)

[michaeldistel]

Closes #72

Summary

• Delete 7 describe blocks (lines 537–1665) from tests/integration/compile.test.ts
• All deleted tests only assert result.ast defined + errors.toHaveLength(0) — identical coverage exists in tests/frontend/parser.test.ts
• Scenarios removed: Expression Parsing, Chained Expressions, Literal Types, Direct Address, Type Declaration, Additional Expression Edge Cases, Multiple POU, Variable Declaration, Control Flow, Complex Program, Edge Cases

Testing

• npm test: 51 files passed, 1339 tests passed, 7 skipped — no regressions