070 eof in subflow impl

✓ Passing This code compiles and runs correctly.

Code

// MUST_FAIL: EOF after subflow impl '=' should produce clear error
// This tests CODEX_REVIEW_FINDINGS CRITICAL #3

~event foo {}
| done {}

~foo =

input.kz

Expected Behavior:

FRONTEND_COMPILE_ERROR

Expected Error:

expected subflow body after '='