feat(libra): add income/expense type filter to transaction history

All / Income / Expenses toggle row with a Filter icon, aligned to the
Calendar-iconed date range row above. Filters transactionsToDisplay
client-side using the existing isIncome/isExpense helpers; works on
top of the search and date filters.

src/modules/expenses/views/TransactionsPage.vue

@@ -17,7 +17,8 @@ import {
   Flag,
   XCircle,
   RefreshCw,
-  Calendar
+  Calendar,
+  Filter
 } from 'lucide-vue-next'
 
 const { user } = useAuth()
@@ -29,6 +30,13 @@ const isLoading = ref(false)
 const dateRangeType = ref<number | 'custom'>(15) // 15, 30, 60, or 'custom'
 const customStartDate = ref<string>('')
 const customEndDate = ref<string>('')
+const typeFilter = ref<'all' | 'income' | 'expense'>('all')
+
+const typeFilterOptions = [
+  { label: 'All', value: 'all' as const },
+  { label: 'Income', value: 'income' as const },
+  { label: 'Expenses', value: 'expense' as const }
+]
 
 function isIncome(t: Transaction): boolean {
   return t.tags?.includes('income-entry') ?? false
@@ -63,9 +71,12 @@ const searchOptions: FuzzySearchOptions<Transaction> = {
   matchAllWhenSearchEmpty: true
 }
 
-// Transactions to display (search results or all transactions)
+// Transactions to display (search results or all transactions), filtered by type
 const transactionsToDisplay = computed(() => {
-  return searchResults.value.length > 0 ? searchResults.value : transactions.value
+  const base = searchResults.value.length > 0 ? searchResults.value : transactions.value
+  if (typeFilter.value === 'income') return base.filter(isIncome)
+  if (typeFilter.value === 'expense') return base.filter(isExpense)
+  return base
 })
 
 // Handle search results
@@ -213,6 +224,22 @@ onMounted(() => {
             </Button>
           </div>
 
+          <!-- Type Filter (All / Income / Expenses) -->
+          <div class="flex items-center gap-2 flex-wrap">
+            <Filter class="h-4 w-4 text-muted-foreground" />
+            <Button
+              v-for="option in typeFilterOptions"
+              :key="option.value"
+              :variant="typeFilter === option.value ? 'default' : 'outline'"
+              size="sm"
+              class="h-8 px-3 text-xs"
+              @click="typeFilter = option.value"
+              :disabled="isLoading"
+            >
+              {{ option.label }}
+            </Button>
+          </div>
+
           <!-- Custom Date Range Inputs -->
           <div v-if="dateRangeType === 'custom'" class="flex items-end gap-2 flex-wrap">
             <div class="flex flex-col gap-1">