Qwen OAuth flow (portal.qwen.ai) stopped working reliably; drop the
executor, registry entry, OAuth provider/service, token refresh
profile, usage handler, and related test coverage and baselines.
Lock current behavior before refactor: buildUrl/buildHeaders per default-executor
provider, translateResponse streaming (claude/gemini), translateRequest body
(openai->claude/gemini/kiro). Sanitize volatile fields (tokens, kimi device-id,
kiro conversationId, timestamps) for stable snapshots.
Co-authored-by: Cursor <cursoragent@cursor.com>
