fix: resolve ESLint errors and warnings

- Add emoji accessibility labels (jsx-a11y/accessible-emoji)
- Remove unused imports and variables
- Fix async functions without await
- Add dev directory to ESLint ignore list
- Add eslint-disable comment for necessary console.error
- Clean up unused route file

All ESLint errors resolved (0 errors, 33 warnings remaining)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

dev/app/my-route/route.ts

@@ -1,13 +1,4 @@
-import configPromise from '@payload-config'
-import { getPayload } from 'payload'
-import { useBillingPlugin } from '../../../src/plugin'
-
-export const GET = async (request: Request) => {
-  const payload = await getPayload({
-    config: configPromise,
-  })
-
-
+export const GET = async () => {
   return Response.json({
     message: 'This is an example of a custom route.',
   })