1968879fe5
Add an "Export chat" button to the AI agent chat window header that downloads the active conversation as a Markdown file. The export is client-only: it serializes the already-loaded persisted message rows (no new network call, no server/DB change) and includes the request internals the chat already holds — tool calls with their input/output, per-message token usage, finish reason and error info. - New util apps/client/src/features/ai-chat/utils/export-chat.ts: buildChatMarkdown() + exportChatAsMarkdown(); reuses tool-parts helpers so tool labels match the on-screen labels; fence() escapes embedded code fences; slugify() yields a safe filename with a chatId fallback; downloads via file-saver's saveAs. - ai-chat-window.tsx: IconFileExport button in the header, shown only for a saved chat with loaded rows (canExport); drag is unaffected. - en-US: add "Export chat" and "You" i18n keys.