Brummel
7ae92d3e60
closes #60 The fixture-corpus filter (NON_PARSEABLE_FIXTURES + list_ail_fixtures) was copy-pasted across three test crates and drifted out of sync as new reject fixtures landed; the examples_dir / workspace_root path walk was reimplemented ~30 more times across the suite, under two spellings (workspace_root / ws_root). Introduce crates/ailang-test-support — a zero-dependency, dev-only leaf crate — as the single home for these helpers: - NON_PARSEABLE_FIXTURES, list_ail_fixtures - workspace_root, examples_dir - canonical_workspace_root (symlink-resolved variant, for the tsan/ race tests that feed the root into native build steps) All integration-test copies across ailang-core, ailang-surface, ailang-prose, ailang-check, and ail now import from the shared crate; the local definitions and their now-orphaned path imports are removed. Path helpers resolve via the support crate's own CARGO_MANIFEST_DIR, so they return the correct absolute paths from any caller. ail_bin helpers are intentionally left in place: they depend on env!("CARGO_BIN_EXE_ail"), which Cargo only defines when compiling the ail crate's own integration tests, so they cannot move to a shared crate. Behaviour-identical: same paths, same fixture lists; full workspace test suite green. Net -177 LOC.