* feat(frontend): add structured human input cards for ask_clarification
Implement a reusable Human Input Card flow for ask_clarification while keeping
the existing text fallback for older clients and IM channels.
Backend:
- Add structured ToolMessage.artifact.human_input payloads for clarification requests.
- Preserve ToolMessage.content as the readable Markdown/text fallback.
- Normalize clarification options from native lists, JSON strings, plain strings,
mixed scalar values, None, and missing options.
- Derive input_mode as choice_with_other when options exist, otherwise free_text.
- Keep disable_clarification non-interactive behavior as a plain ToolMessage with
no human_input artifact.
- Cover artifact persistence and Gateway message metadata preservation in tests.
Frontend:
- Add human input protocol types, runtime guards, extractors, response builders,
and thread-state helpers.
- Add reusable HumanInputCard with option buttons, free-text input, pending,
read-only, disabled, and answered states.
- Render structured clarification cards from artifact.human_input, with Markdown
fallback for malformed or legacy tool messages.
- Preserve line breaks in structured question/context/option text.
- Hide submitted clarification bridge messages from the chat UI via
additional_kwargs.hide_from_ui.
- Send structured human_input_response metadata through the fourth sendMessage
options argument, preserving run context in the third argument.
- Wire submissions for normal chats, custom agent chats, agent bootstrap chats,
and sidecar chats.
- Derive answered state from raw thread.messages so hidden replies still update
the original card.
- Clear pending state when the hidden reply arrives, dispatch is dropped, or a
later async stream failure appears on thread.error.
* perf(frontend): optimize HumanInputCard UI interactions
- Support Enter key to submit text input (Shift+Enter for newline)
- Render question and context fields as Markdown instead of plain text
- Replace deprecated FormEventHandler type with structural typing
* test(frontend): add unit test cover optimize HumanInputCard UI interactions
* feat(frontend): disabled chatbox when has new human-input-card
* fix(style): lint error fix
* fix: sanitize hidden human input replies
- Preserve IME composition safety for human input card Enter submits
- Treat hidden human input responses as genuine user messages for sanitization
- Keep hidden card replies in memory filtering while excluding malformed/internal hidden messages
- Add regression coverage for card IME handling and hidden reply sanitization
* fix: tighten human input response validation
- Reject empty hidden human input response values
- Remove invalid list ARIA role from human input card options
- Add backend coverage for empty response payloads
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Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
