Inference Gateway Proposal process

Our current proposal process is intentionally light-weight. If you have a proposal you are interested in sharing, please follow these steps:

1. Cut an issue or bring a topic to the weekly meeting!
2. Assuming positive signal, or if more context is needed please add a proposal, following the style and naming conventions shown here: https://github.com/kubernetes-sigs/gateway-api-inference-extension/tree/main/docs/proposals