Add holistic table event processing benchmark
Add an order-management workload to measure backend event performance beyond counter increments. Six events filter and sort 1,000 dataclass rows, recompute totals, generate deltas, and serialize StateUpdate envelopes through Reflex's JSON encoder.
The benchmark warms state before timing and returns to the same filter and sort direction after each sample. A separate correctness test verifies serialized rows and totals across repeated batches. The README documents how to run it and the measurement boundary: processor lifecycle is included; hydration, network transport, database access, and browser rendering are excluded.
Related to #7056, which includes the original benchmark alongside runtime optimizations. This PR isolates the benchmark and adds repeatable samples, correctness assertions, and run documentation. Encoding is measured through json_dumps; changes confined to Socket.IO's encoder configuration require updating the benchmark's encoder too.
Validation
- Event tests: 3 passed.
- CodSpeed mode: 2 benchmarks passed, correctness test deselected.
- Commit hooks: Ruff formatting/checks, codespell, stub update, Pyright, and ty passed.
- Full
uv run pyright reflex tests: passed. -
git diff --check: passed.
Repository-wide Ruff checks report unrelated existing issues under .states.bak/ and ignore/. The full unit suite was not run; this change only adds benchmark coverage and documentation.
No package source or public behavior changes; no changelog fragment included.