Three improvements to the query parser, all aimed at allowing query
patterns to refer to unnamed tokens:
1. Bare-literal capture: `"=" @op` now captures the unnamed `=` token,
matching the parenthesized form `("=") @op`. Previously the literal
branch in parse_query_list skipped the maybe_wrap_capture call, so
the `@op` was a leftover token and would error.
2. Bare `_` matches any node, named or unnamed. Previously bare `_` and
`(_)` both produced QueryNode::Any with the same matches_named_only
behaviour, so bare `_` would skip unnamed children. Now Any carries a
match_unnamed flag: false for `(_)` (named-only, tree-sitter default)
and true for bare `_` (any node).
3. Named fields and bare child patterns may be intermixed in any order.
Previously, once parse_query_fields saw a bare pattern it would stop
accepting named fields. The fix accumulates bare patterns into the
implicit `child` field and keeps parsing.
Each named field independently selects its target field for matching, so
the source-order of fields in the query is purely cosmetic and intermixing
is safe.
Add tests covering parenthesized capture, bare-literal capture, and the
named-vs-any distinction between `(_)` and bare `_`. Update query-syntax
docs to reflect all three.
Add BUILD.bazel files for the yeast and yeast-macros crates, register
them as dependencies of the shared tree-sitter extractor, and refresh
the vendored crate dependencies via update_tree_sitter_extractors_deps.sh.
