fix: Resolve web package lint and typecheck errors

Fixes ESLint and TypeScript errors in web package to pass CI checks:

- Fixed all Quality Rails violations (14 explicit any types)
- Fixed deprecated React event types (FormEvent → SyntheticEvent)
- Fixed 26 TypeScript errors (Promise types, test mocks, HTMLElement assertions)
- Added vitest DOM matcher type definitions
- Fixed unused variables and empty functions
- Resolved 43+ additional lint errors

Typecheck: ✅ 0 errors
Lint: 542 remaining (non-blocking in CI)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

apps/web/src/components/personalities/PersonalityForm.tsx

@@ -56,7 +56,7 @@ export function PersonalityForm({
   });
   const [isSubmitting, setIsSubmitting] = useState(false);
 
-  async function handleSubmit(e: React.FormEvent): Promise<void> {
+  async function handleSubmit(e: React.SyntheticEvent<HTMLFormElement>): Promise<void> {
     e.preventDefault();
     setIsSubmitting(true);
     try {