feat(defter): hafta seçici ve hızlı harcama giriş formu

- /defter: önceki/sonraki/bu hafta, haftanın harcanan/bütçe toplamı
- Form: tutar, 4 grup düğmesi, kategori ve ödeme türü seçimi, tarih, açıklama
- Son seçimler bu cihazda hatırlanır; sunucu hataları ilgili alana düşer

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/features/ledger/page.tsx

@@ -1,11 +1,78 @@
-import { ComingSoon, PageHeader } from '@/components/page'
+import { useState } from 'react'
+import { useSearchParams } from 'react-router'
+import { PageError, PageHeader, PageLoading } from '@/components/page'
+import { NoPeriodCard } from '@/features/period-wizard/no-period-card'
+import { Section } from '@/features/planning/plan-read'
+import { useCategories, usePaymentMethods } from '@/lib/catalog'
+import { toIsoDate } from '@/lib/format'
+import { parseWeekParam, weekIndexFor } from '@/lib/ledger'
+import { useBudget, useCurrentPeriod } from '@/lib/periods'
 import { t } from '@/lib/strings'
+import type { Period } from '@/types/Period'
+import { EntryForm } from './entry-form'
+import { WeekPicker } from './week-picker'
 
 export function LedgerPage() {
+  const current = useCurrentPeriod()
   return (
     <>
       <PageHeader title={t.pages.ledger.title} description={t.pages.ledger.description} />
-      <ComingSoon when="Faz 5'te" />
+      {current.isPending ? (
+        <PageLoading />
+      ) : current.isError ? (
+        <PageError message={current.error.message} onRetry={current.refetch} />
+      ) : current.data ? (
+        <LedgerView period={current.data} />
+      ) : (
+        <NoPeriodCard />
+      )}
     </>
   )
 }
+
+/** Hafta adreste tutulur (`?hafta=2`): yenileyince / geri gelince aynı hafta açılır. */
+function LedgerView({ period }: { period: Period }) {
+  const [params, setParams] = useSearchParams()
+  const [today] = useState(() => toIsoDate(new Date()))
+  const inPeriod = today >= period.start_date && today <= period.last_date
+  const todayIndex = inPeriod ? weekIndexFor(period.weeks, today) : null
+  const index =
+    parseWeekParam(params.get('hafta'), period.weeks.length) ?? weekIndexFor(period.weeks, today)
+  const week = period.weeks[index - 1]
+
+  const budget = useBudget(period.id)
+  const categories = useCategories()
+  const methods = usePaymentMethods()
+
+  const goTo = (n: number) =>
+    setParams(n === todayIndex ? {} : { hafta: String(n) }, { replace: true })
+
+  const failed = [categories, methods].find((q) => q.isError)
+  return (
+    <div className="mx-auto max-w-3xl space-y-4">
+      <WeekPicker
+        weeks={period.weeks}
+        index={index}
+        todayIndex={todayIndex}
+        budget={budget.data}
+        onChange={goTo}
+      />
+      <Section title={t.ledger.formTitle}>
+        {failed?.error ? (
+          <PageError message={failed.error.message} onRetry={failed.refetch} />
+        ) : !categories.data || !methods.data ? (
+          <PageLoading />
+        ) : (
+          <EntryForm
+            period={period}
+            week={week}
+            today={today}
+            categories={categories.data}
+            methods={methods.data}
+            onSaved={(date) => goTo(weekIndexFor(period.weeks, date))}
+          />
+        )}
+      </Section>
+    </div>
+  )
+}