[Feature] EAGLE3.1 support

[bluecoffee8]

Checklist

• 1. If the issue you raised is not a feature but a question, please raise a discussion at https://github.com/sgl-project/SpecForge/discussions/new/choose Otherwise, it will be closed.
• 2. Please use English, otherwise it will be closed.

Motivation

Any official plans to support EAGLE 3.1 training? I am currently investigating this and may have some code ready. Will update this post and open a PR later with some results. See: [https://github.com//pull/568]
Links:

• https://vllm.ai/blog/2026-05-26-eagle-3-1
• feat: support post-norm architecture lightseekorg/TorchSpec#97

Related resources

No response