071 reject terminal before effect at dispatch

// ============================================================================
// Test 210_071: MUST_FAIL — effect handlers must precede terminal handlers
//                          at the consumer dispatch site.
//
// Per docs/EFFECT_BRANCHES.md the ordering rule applies at both event decl
// AND dispatch. A consumer that lists `| done` above `! each` is rejected
// by the parser.
//
// The well-formed shape (defended by 210_073) is:
//   ~count-to-three = for(0..3)
//   ! each _ |> std/io:print.ln("counting")
//   | done |> result 3
// ============================================================================

~pub event for { start: usize, end: usize }
! each usize
| done usize

~for(start: 0, end: 3)
| done _ |> _
! each _ |> _