follow-up: add WASM julia regression test for macro signature guard

[carlos-alm]

Deferred from PR #1130 review.

Original reviewer comment: #1130 (review)

Greptile's review summary on #1130 flagged that the new handleCall guard in src/extractors/julia.ts now skips both function_definition and macro_definition grandparents, but only the function branch had a regression test (does not record function signature as call). The macro branch is uncovered, so a future grammar-related regression on macro_definition would go undetected at the WASM layer.

Context: A test was prepared on the head branch (commit 6ae097b on fix/1126-julia-wasm-extractor-bugs) but landed after the PR was squash-merged, so it's not in the merged history.

Suggested fix: Add a test mirroring the function-signature case but for macros — e.g.:

it('does not record macro signature as call', () => {
  const symbols = parseJulia(`macro mymac(x)
    println(x)
end`);
  const callNames = symbols.calls.map((c) => c.name);
  expect(callNames).not.toContain('mymac');
  expect(callNames).toContain('println');
});

File: tests/parsers/julia.test.ts