tree-sitter query compilation (used to set up language grammars) is a
significant bottleneck in test setup. Profiling showed rust_lang()
creation taking ~270ms per test in dev builds, with nearly all time
spent in tree-sitter's query compiler.

With opt-level = 3, this drops to ~63ms locally — a 4x speedup on that
step. Across hundreds of tests that create language grammars (vim,
editor, collab, etc.), this ought to save substantial CI time.



Release Notes:

- N/A or Added/Fixed/Improved ...