Dev UI never shows what the human answered in a HITL form

> Dev UI issue (prebuilt `adk-web` bundle served by `adk web`) — please transfer to google/adk-web if that is the right home.

A reply submitted through the inline HITL form renders as an opaque `✓ adk_request_input` chip with no text, while the same answer typed into the main chat box renders as a normal readable bubble. For an approval gate the transcript is the audit trail, and "someone answered, contents withheld" is the one thing it must not say.

```
cd dev && npx adk web ../samples/workflows/dynamic --port 8132
# app=human_input: send "please delete the staging database",
# then type "yes" into the inline "Enter your response..." form
```

```
#3 check / adk_request_input / person <- this IS the human's "yes", rendered with no text
#4 Approved

vs. answering the same interrupt in the main chat box:
#7 no
#8 Denied
```

The answer is present in the session (`response: {"result": "yes"}`); it takes selecting the event and opening the raw-JSON tab to see it.