fix(ui): resolve TypeScript errors blocking production build

[dimakis]

Summary

• Fix 20+ TypeScript strict mode errors across the UI codebase that prevented npm run build (and thus make run-prod) from succeeding
• Errors had accumulated because the Vite dev server doesn't enforce type checking, so they were invisible during development
• Fixes include: typed vitest mocks, removed unused imports/variables, Framer Motion ease tuple assertions, missing Proposal type fields, Recharts label prop types, and vitest/config import for vite.config.ts

Motivation

Production containerized build (make run-prod) fails at the UI build step due to TypeScript errors that the dev server silently ignores.

Type of Change

• fix — Bug fix

Changes

20 files changed (43 insertions, 56 deletions — net reduction):

Category	Files	Fix
Mock types	trace-event-handler.test.ts	Typed vi.fn<SetActivityFn>() for vitest 4.x
Duplicate types	env.ts, vite-env.d.ts	Removed duplicate Window.__ENV__ declaration
Unused code	8 files	Removed unused imports and dead variables
Framer Motion	EmptyState.tsx, MessageBubble.tsx	Cast ease arrays as [number, number, number, number] tuples
Missing types	types.ts	Added ha_automation_id, ha_disabled, ha_error to Proposal
Recharts	usage.tsx	Fixed Pie label props and Tooltip formatter types
Vitest config	vite.config.ts	Switched to import { defineConfig } from "vitest/config"
React 19	useGlobalActivityStream.ts	Added explicit initial value to useRef
Missing arg	InlineAssistant.tsx	Provided required 3rd argument to handleTraceEvent

Testing

• npx tsc --noEmit — zero errors
• npm run build (tsc -b && vite build) — completes successfully
• make run-prod — builds and starts the containerized stack

Security Considerations

• No security implications

Checklist

• My code follows the project's style (ruff, mypy pass)
• I've updated documentation if needed
• I've added conventional commit messages
• Branch commits squashed into a single conventional commit
• Ready for rebase-merge