Model downloads send GITHUB_TOKEN to any URL that contains "github.com" #504

baseHeaders() in src/local-llm/download-attempt.ts:64 decides whether to attach GITHUB_TOKEN / GH_TOKEN with a substring check:

url.includes("github.com") || url.includes("githubusercontent.com")

Any URL with that text anywhere gets the token, for example https://example.com/github.com/model.gguf or a host like github.com.example.net. Custom models accept arbitrary huggingFaceUrl / mmprojUrl values, so a crafted model link in config is enough to send an exported GitHub token to a third-party server. The check also runs before the Hugging Face branch, so a Hugging Face URL whose path contains "github.com" gets the GitHub token instead of the HF one.

The same class of bug was already fixed for HF_TOKEN, which now goes only to Hugging Face hosts via isHuggingFaceUrl().

Suggested fix: parse the URL and compare the hostname exactly (github.com, api.github.com, objects.githubusercontent.com, raw.githubusercontent.com), require https:, and add a test for a lookalike host and a lookalike path.

Found in v0.6.4 (3cbc58f).