Rewrite mirror-to-gitee.yml to push main + tags to the Gitee mirror using
HTTPS + GITEE_TOKEN (reusing the existing secret) instead of hub-mirror-action
+ an SSH key. Gated on GITEE_TOKEN; needs GITEE_USER + GITEE_REPO secrets.
Keeps Gitee code/raw in sync automatically on every push to main + tags, so
no more manual git push after each release.