Add tool response to session log entry

What does this MR do and why?

Renders tool response data in the Duo Agents Platform session log entry component. When a tool call includes a tool_response field in its toolInfo, a second MessageToolKvSection is now displayed below the existing "Request" section showing the response.

Also fixes an i18n inconsistency where the "Request" title was a bare string instead of being wrapped in s__(), and replaces a fragile singular findToolKvSection test helper with the safer findAllToolKvSections().at(0).

References

#562508 (closed)

Screenshots or screen recordings

How to set up and validate locally

1. Navigate to a Duo Agents workflow session that has tool calls with responses (this merged recently so you may need to make a new one)
2. Expand a tool call log entry
3. Verify both "Request" and "Response" sections are rendered
4. Verify that tool calls without a tool_response only show the "Request" section

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