Picohttpparser

[cs01]

Replace libwebsockets with libuv + picohttpparser

Summary

Replace the libwebsockets HTTP server backend with libuv TCP + picohttpparser, improving HTTP throughput from 3,600 req/s to 15,571 req/s (4.3x).

• Rewrite lws-bridge.c to use libuv for TCP and picohttpparser for zero-copy HTTP parsing, keeping the same C API (lws_bridge_serve, lws_bridge_ws_send, lws_bridge_ws_broadcast) so the LLVM IR codegen needs zero changes
• WebSocket support preserved via embedded SHA-1 + base64 handshake and frame parser (~100 lines), removing the OpenSSL dependency for WS
• Vendor picohttpparser (~300 lines, MIT, from H2O project) as a build-time dependency, remove libwebsockets (~100K lines)
• Unify event loops: httpServe() now runs on uv_default_loop() instead of its own lws_service() loop, fixing the bug where httpServe() and setTimeout() couldn't coexist
• Optimize HTTP hot path: eliminate per-response malloc/free by embedding write buffers in the connection struct, replace snprintf with memcpy of static header prefixes + fast itoa, shrink http_conn_t from ~1MB to ~15KB by heap-allocating the request body on demand
• Fix C benchmark to use epoll instead of blocking single-connection I/O for an apples-to-apples comparison

Benchmark results

Runtime	Before	After
ChadScript	3,603 req/s	17,770 req/s
Go	16,420	17,804
Node.js	17,552	17,223
Bun	16,446	17,421
C (epoll)	11,052	15,249

50 concurrent connections, 10s duration, Hello World handler.

Files changed

File	Change
c_bridges/lws-bridge.c	Complete rewrite: libuv TCP + picohttpparser + embedded WS + hot path optimization
bench/http/c-server.c	Rewrite C benchmark to use epoll for fair async I/O comparison
scripts/build-vendor.sh	Remove libwebsockets, add picohttpparser, fix build order
src/compiler.ts	Update linker flags (drop -lwebsockets, add picohttpparser.o, add usesMongoose to libuv condition)
src/native-compiler-lib.ts	Same linker flag updates for the native compiler driver
src/codegen/llvm-generator.ts	Add usesMongoose to needsLibuv condition
.github/workflows/ci.yml	Replace libwebsockets.a with picohttpparser.o in vendor checks and release packaging
docs/public/benchmarks.json	Updated HTTP server benchmark numbers

Test plan

• npm test — 168/168 tests pass
• node --import tsx --test tests/http-routes.test.ts — 16/16 HTTP tests pass (routes, POST body, query params, status codes, deflate, zstd, concurrent requests, keepalive)
• npm run verify:quick — self-hosting passes (Stage 0 + Stage 1)
• bash bench/run-http.sh — benchmark confirms improvement