Addresses FLAG 1 and FLAG 2 from the 7-Gate review on PR #20.
FLAG 1 (token persisted on disk):
Previous: `git clone https://x-access-token:${GITHUB_TOKEN}@github.com/...` wrote
the full tokenized URL into /workspace/repo/.git/config as `[remote "origin"] url = …`.
Token survived container restarts on any bind-mounted workspace_dir.
Fix: after clone, `git remote set-url origin https://github.com/${GITHUB_REPO}.git`
scrubs the token from the remote URL. Token is only in the clone command's argv
(transient) and not persisted on disk. Falls back to anonymous for public repos.
FLAG 2 (docs not updated):
Added GITHUB_REPO and GITHUB_TOKEN entries under a new 'GitHub' section in
.env.example with notes about (a) what they're read for, (b) that GITHUB_TOKEN
should be registered as a global secret via POST /admin/secrets, (c) how it's
handled to avoid on-disk persistence.
FLAG 3 (per-workspace gating) is deferred to a separate issue — it's a platform
design question about secret scope/ACLs, not a template fix.
cd739ef299