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## Summary Fix a memory leak in `RequestContext.doRenderWithBody()` where `Strong.Impl` memory was leaked when proxying streaming responses through Bun's HTTP server. ## Problem When a streaming response (e.g., from a proxied fetch request) was forwarded through Bun's server: 1. `response_body_readable_stream_ref` was initialized at line 1836 (from `lock.readable`) or line 1841 (via `Strong.init()`) 2. For `.Bytes` streams with `has_received_last_chunk=false`, a **new** Strong reference was created at line 1902 3. The old Strong reference was **never deinit'd**, causing `Strong.Impl` memory to leak This leak accumulated over time with every streaming response proxied through the server. ## Solution Add `this.response_body_readable_stream_ref.deinit()` before creating the new Strong reference. This is safe because: - `stream` exists as a stack-local variable - JSC's conservative GC tracks stack-local JSValues - No GC can occur between consecutive synchronous Zig statements - Therefore, `stream` won't be collected between `deinit()` and `Strong.init()` ## Test Added `test/js/web/fetch/server-response-stream-leak.test.ts` which: - Creates a backend server that returns delayed streaming responses - Creates a proxy server that forwards the streaming responses - Makes 200 requests and checks that ReadableStream objects don't accumulate - Fails on system Bun v1.3.5 (202 leaked), passes with the fix ## Related Similar to the Strong reference leak fixes in: - #23313 (fetch memory leak) - #25846 (fetch cyclic reference leak)