RPC module augmentation stopped working in 0.4.x

[mark-tomlinson-dev]

Describe the bug

The declare module augmentation shown in the RPC docs appears to no longer register custom RPC function names. Calling one via rpc.call() fails to type-check from 0.4.x onwards.

Thank you for an awesome tool!

Reproduction

https://github.com/mark-tomlinson-dev/devtools-kit-rpc-augmentation-repro

System Info

System:
    OS: macOS 14.3
    CPU: (8) arm64 Apple M3
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.12.0
    npm: 10.9.0
    pnpm: 10.33.0
  npmPackages:
    @vitejs/devtools-kit: 0.4.12 (also fails on 0.6.1, works on 0.1.13)
    typescript: 5.9.3

Used Package Manager

pnpm

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