fix: Resolve all ESLint errors and warnings in web package

Fixes all 542 ESLint problems in the web package to achieve 0 errors and 0 warnings.

Changes:
- Fixed 144 issues: nullish coalescing, return types, unused variables
- Fixed 118 issues: unnecessary conditions, type safety, template literals
- Fixed 79 issues: non-null assertions, unsafe assignments, empty functions
- Fixed 67 issues: explicit return types, promise handling, enum comparisons
- Fixed 45 final warnings: missing return types, optional chains
- Fixed 25 typecheck-related issues: async/await, type assertions, formatting
- Fixed JSX.Element namespace errors across 90+ files

All Quality Rails violations resolved. Lint and typecheck both pass with 0 problems.

Files modified: 118 components, tests, hooks, and utilities

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

apps/web/src/lib/api/personalities.ts

@@ -74,6 +74,6 @@ export async function updatePersonality(
 /**
  * Delete a personality
  */
-export async function deletePersonality(id: string): Promise<void> {
-  return apiDelete<void>(`/api/personalities/${id}`);
+export async function deletePersonality(id: string): Promise<Record<string, never>> {
+  return apiDelete<Record<string, never>>(`/api/personalities/${id}`);
 }