Release v0.4.9 The cold-concurrent worker-corruption class is closed (ext pin v0.3.52, S5b v2 per-coroutine object-static isolation — ext#44/#48/#49). Rolls the large cluster since 0.4.0: session security + correctness, exit/die HaltException, #379 session persistence, the output-buffer 0-byte-body fix, ZealAPI scope + mode-aware null, the isolation-stage taxonomy, and the just-works roadmap. Also: uniform $app->App-instance injection, per-verb route helpers, README stars-badge fix, Cache stampede-lock test-isolation fix.