fix: production readiness — resolve build, lint, and code quality issues

- Fix Next.js build failure: remove duplicate route at (dashboard)/listings/[id]
  that conflicted with (public)/listings/[id] (same URL path in two route groups)
- Fix 772 ESLint errors: auto-fix import ordering (import-x/order), remove unused
  imports/variables, convert empty interfaces to type aliases, replace require()
  with ESM imports, fix consistent-type-imports violations
- Add CLAUDE.md for developer onboarding documentation
- All checks pass: 0 lint errors, typecheck clean, 230 tests passing, build success

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/components/ui/badge.tsx

@@ -1,5 +1,5 @@
-import * as React from 'react';
 import { cva, type VariantProps } from 'class-variance-authority';
+import * as React from 'react';
 import { cn } from '@/lib/utils';
 
 const badgeVariants = cva(

apps/web/components/ui/button.tsx

@@ -1,5 +1,5 @@
-import * as React from 'react';
 import { cva, type VariantProps } from 'class-variance-authority';
+import * as React from 'react';
 import { cn } from '@/lib/utils';
 
 const buttonVariants = cva(

apps/web/components/ui/input.tsx

@@ -1,7 +1,7 @@
 import * as React from 'react';
 import { cn } from '@/lib/utils';
 
-export interface InputProps extends React.InputHTMLAttributes<HTMLInputElement> {}
+export type InputProps = React.InputHTMLAttributes<HTMLInputElement>;
 
 const Input = React.forwardRef<HTMLInputElement, InputProps>(
   ({ className, type, ...props }, ref) => {

apps/web/components/ui/label.tsx

@@ -1,7 +1,7 @@
 'use client';
 
-import * as React from 'react';
 import { cva, type VariantProps } from 'class-variance-authority';
+import * as React from 'react';
 import { cn } from '@/lib/utils';
 
 const labelVariants = cva(

apps/web/components/ui/select.tsx

@@ -1,7 +1,7 @@
 import * as React from 'react';
 import { cn } from '@/lib/utils';
 
-export interface SelectProps extends React.SelectHTMLAttributes<HTMLSelectElement> {}
+export type SelectProps = React.SelectHTMLAttributes<HTMLSelectElement>;
 
 const Select = React.forwardRef<HTMLSelectElement, SelectProps>(
   ({ className, children, ...props }, ref) => {

apps/web/components/ui/textarea.tsx

@@ -1,7 +1,7 @@
 import * as React from 'react';
 import { cn } from '@/lib/utils';
 
-export interface TextareaProps extends React.TextareaHTMLAttributes<HTMLTextAreaElement> {}
+export type TextareaProps = React.TextareaHTMLAttributes<HTMLTextAreaElement>;
 
 const Textarea = React.forwardRef<HTMLTextAreaElement, TextareaProps>(
   ({ className, ...props }, ref) => {