repo_tree: GET /git/trees/{ref}?recursive=1 — full recursive file tree
repo_topics_update: PUT /repos/{owner}/{repo}/topics — replace topic list
file_read: detect array response and return descriptive error for dir paths
repo_create: POST /user/repos or /orgs/{org}/repos, is_org flag routes
repo_update: PATCH /repos/{owner}/{repo}, confirm required when private=false
repo_mirror_push: add/list/delete push mirrors, password never returned
Shared LRU avoids repeated Gitea calls for default-branch resolution;
the simple stdlib map alternative would race on concurrent access without
a mutex per entry, which is more code than the LRU.
