Return Pi TUI Text component for villani-result to prevent crash

[mmprotest]

Motivation

• The Pi custom renderer for villani-result returned a plain string which caused Pi to crash with child.render is not a function when Pi tried to render the final message.
• The goal is to make the final durable message renderable by returning a Pi TUI component while preserving the structured durable message payload and existing bridge/proxy logic.

Description

• Import Text from @earendil-works/pi-tui and change renderVillaniResultMessage to return a Text component instead of a raw string in integrations/pi-villani/src/render.ts.
• Add extractVillaniResultText(message) to safely extract final text from string, text-part arrays, and object shapes, and prepend a themed label when theme.fg is provided.
• Keep sendDurableVillaniMessage unchanged in payload shape so durable messages remain structured with customType: "villani-result" and content: [{type:"text", text: ...}] for Pi compatibility.
• Add @earendil-works/pi-tui as a peerDependency and pin it as a devDependency for build/test resolution in integrations/pi-villani/package.json (and update lockfile).
• Expand Node tests in integrations/pi-villani/src/extension.test.ts to assert the renderer returns an object with a render() method, handle string and array content shapes, and ensure final rendering does not throw.

Testing

• Ran cd integrations/pi-villani && npm run build and the TypeScript build succeeded.
• Ran cd integrations/pi-villani && npm test and the test suite passed (77 tests passed, 0 failures).
• All new/modified tests for renderVillaniResultMessage and sendDurableVillaniMessage passed.

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Codex Task