Fix connection event being emitted multiple times per socket in node:http

[heimskr]

What does this PR do?

Fixes a bug where node:http servers would emit connection events multiple times for the same socket. This would cause Vite to accumulate excess close listeners on sockets.

• Documentation or TypeScript types
• Code changes

How did you verify your code works?

I ran an example Vite app (/examples/web in sroussey/ellmers) and spammed refresh in Firefox while checking for warnings about too many close listeners. I also ran the node:http tests.

[robobun]

^{Updated 8:45 PM PT - Mar 18th, 2025}

❌ @heimskr, your commit d59817a has 2 failures in Build #13495:

• test/napi/napi.test.ts - 56 failing on 🪟 2019 x64
• test/napi/napi.test.ts - 56 failing on 🪟 2019 x64-baseline
• test/napi/napi-value-ffi.test.ts - 2 failing on 🪟 2019 x64
• test/napi/napi-value-ffi.test.ts - 2 failing on 🪟 2019 x64-baseline

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🧪   try this PR locally:

bunx bun-pr 18295