Bun 1.3.13: Bun.file().stream() ends process stdin, killing MCP stdio servers

An MCP stdio server run with Bun 1.3.13 quietly exited after every upload. Iterating Bun.file(path).stream() (used to MD5 the file before uploading) ends the process's stdin, so the StdioServerTransport sees EOF and the server quits once idle. The host (VoiceOS) then marks the integration 'error' and drops its tools without reconnecting. Reading through node:fs/promises (or node:fs createReadStream) avoids it, and Bun 1.3.14 doesn't have the bug. Gotcha: VoiceOS resolves bun from PATH (~/.bun/bin first), not its bundled runtime, so test with the Bun the host actually picks. Add a test that runs the real read in a child process with a live stdin pipe and checks stdin stays open.