feat: category import from CSV + budget auto-assign rules

Category:
- Add categoryColumn to NormalizerConfig and NormalizedRow
- Map 'Category' column for Discover CC profile
- Write category to Transaction on upload

Budget rules:
- Add BudgetRule model (userId, budgetId, pattern)
- API: GET/POST /api/budget-rules, DELETE /api/budget-rules/:id
- Apply rules during upload (first case-insensitive match wins)
- Budgets page fetches and passes rules per budget
- BudgetCard 'Rules' menu item opens BudgetRulesDialog for add/delete

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

src/app/(app)/budgets/page.tsx

@@ -6,29 +6,41 @@ export default async function BudgetsPage() {
   const session = await auth()
   if (!session?.user?.id) return null
 
+  const userId = session.user.id
   const now = new Date()
   const monthStart = new Date(now.getFullYear(), now.getMonth(), 1)
   const monthEnd = new Date(now.getFullYear(), now.getMonth() + 1, 0, 23, 59, 59, 999)
 
-  const [budgets, spendRows] = await Promise.all([
+  const [budgets, spendRows, rules] = await Promise.all([
     prisma.budget.findMany({
-      where: { userId: session.user.id },
+      where: { userId },
       orderBy: { createdAt: 'asc' },
     }),
     prisma.$queryRaw<{ budgetId: string; total: bigint }[]>`
       SELECT t."budgetId", COALESCE(SUM(t."amountCents"), 0)::bigint AS total
       FROM "Transaction" t
       JOIN "Account" a ON t."accountId" = a.id
-      WHERE a."userId" = ${session.user.id}
+      WHERE a."userId" = ${userId}
         AND t."budgetId" IS NOT NULL
         AND t.type = 'DEBIT'
         AND t.date >= ${monthStart}
         AND t.date <= ${monthEnd}
       GROUP BY t."budgetId"
     `,
+    prisma.budgetRule.findMany({
+      where: { userId },
+      orderBy: { createdAt: 'asc' },
+      select: { id: true, budgetId: true, pattern: true },
+    }),
   ])
 
   const spendMap = new Map(spendRows.map((r) => [r.budgetId, Number(r.total)]))
+  const rulesMap = new Map<string, { id: string; pattern: string }[]>()
+  for (const rule of rules) {
+    const existing = rulesMap.get(rule.budgetId) ?? []
+    existing.push({ id: rule.id, pattern: rule.pattern })
+    rulesMap.set(rule.budgetId, existing)
+  }
 
   const budgetsWithSpend = budgets.map((b) => ({
     id: b.id,
@@ -37,6 +49,7 @@ export default async function BudgetsPage() {
     color: b.color,
     isActive: b.isActive,
     spendCents: spendMap.get(b.id) ?? 0,
+    rules: rulesMap.get(b.id) ?? [],
   }))
 
   return (