Remove unused icon component and Rive AI-icon hook

[wojtekn]

Related issues

• N/A

How AI was used in this PR

Follow-up to #4293. Used Claude Code with Knip to identify unused UI code, then manually verified each finding had no references (including dynamic/string references and test mocks) before removing it. The Rive removal footprint (asset, test mock, dependency, and Vite bundling) was traced by hand.

Proposed Changes

Removes two pieces of dead UI code and their supporting infrastructure. No user-visible impact — neither was rendered anywhere. This trims an unused animation dependency and its WASM bundling, slightly reducing install and build surface.

• Removes an unused SVG icon component that nothing referenced.
• Removes the unused animated AI icon hook along with its Rive animation asset, its test mock, the @rive-app/react-canvas dependency, and the Rive-specific WASM copying in the Electron Vite config.

Testing Instructions

• npm run typecheck passes across all workspaces.
• npm test -- apps/studio passes (684 tests) — confirms removing the use-ai-icon test mock had no fallout.
• npx knip no longer reports the two icons, and @rive-app/* is fully gone from the dependency graph.
• Smoke-test the app (especially the AI/assistant surfaces) to confirm no missing-icon regression

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[wpmobilebot]

📊 Performance Test Results

Comparing 9cfb1cb vs trunk

app-size

Metric	trunk	9cfb1cb	Diff	Change
App Size (Mac)	1362.04 MB	1358.38 MB	3.66 MB	🟢 -0.3%

site-editor

Metric	trunk	9cfb1cb	Diff	Change
load	1111 ms	1049 ms	62 ms	🟢 -5.6%

site-startup

Metric	trunk	9cfb1cb	Diff	Change
siteCreation	6517 ms	6541 ms	+24 ms	⚪ 0.0%
siteStartup	2388 ms	2394 ms	+6 ms	⚪ 0.0%

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Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change (<50ms diff)