fix: stabilize deploy validation

[kentcdodds]

Summary

• lint repository areas in isolated sequential processes so TypeScript state is released and memory remains bounded
• eagerly prebundle dependencies for both solution servers and the shared renderer
• mount renderer iframes only after the real postMessage listener is active, and bridge action responses deterministically
• install Chromium on Node 22 and keep one CI-owned renderer alive across the complete solution suite
• preserve every solution test and its behavioral assertions, with 10-second browser-event ceilings under CI load

Failure addressed

Deploy workflow run https://github.com/epicweb-dev/mcp-ui/actions/runs/30413812797 failed because monolithic ESLint accumulated beyond the Node heap on macOS and Windows, while Vite invalidated newly discovered prebundles before Vitest discovered or completed test files.

Validation

• npm run lint
• npm run typecheck
• Chromium installs with Linux dependencies on the browser job’s Node 22 runtime
• Setup passes on Node 26 across Linux, macOS, and Windows
• shared renderer exits are propagated immediately
• real iframe lifecycle and action messages remain the source of test assertions
• current PR CI is the final source of truth

  

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