Fix TypeScript compile errors blocking Docker build

- Add vite-env.d.ts for import.meta.env type support
- Remove unused imports: ChevronRight, useCallback (x2), today
- Silence unused attachments state read (keep setter for future use)
- Fix FloatManagement changeTinTargets reducer: drop unused k, fix v type

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/pages/DailyCashUp.tsx

@@ -1,4 +1,4 @@
-import { useState, useCallback } from 'react'
+import { useState } from 'react'
 import { RefreshCw, Save, CheckCircle, Loader } from 'lucide-react'
 import { api } from '../api'
 import { PageHeader, Card, Btn, StatusBadge } from '../components/Layout'
@@ -38,7 +38,7 @@ export function DailyCashUp({ user: _user }: Props) {
   const [float, setFloat] = useState<Denomination[]>(initDenominations('float'))
   const [machines, setMachines] = useState<CardMachine[]>(initMachines())
   const [notes, setNotes] = useState('')
-  const [attachments, setAttachments] = useState<Attachment[]>([])
+  const [, setAttachments] = useState<Attachment[]>([])
   const [newbookTotals, setNewbookTotals] = useState<PaymentTotals | null>(null)
   const [tillPayments, setTillPayments] = useState<TillPayment[]>([])
   const [fetching, setFetching] = useState(false)