fix: move IMA_HEADERS before rebuildCookieState to avoid TDZ error

fix: API keys now use env-only when IMA_API_KEYS is set; reject non-ASCII placeholder cookies

fix: actually read IMA_API_KEYS from environment variables

fix: use Set.size, show short keys in startup log

fix: read PORT from process.env first, add startup logs

fix: remove all CJK/garbled characters for HF Docker compatibility

fix: text extraction bypass, stderr diagnostics, OpenAI ensureBlock removal

fix: 正文被误归为思考内容

fix: 思考内容可见 + Anthropic 流式协议修复