Merge branch 'fix/calculation-accuracy' into main

Combines the decimal migration (int cents → decimal.Decimal via
shopspring/decimal) with main's handler refactor (split space.go into
domain handlers, WithTx/Paginate helpers, recurring deposit removal).

- Repository layer: WithTx pattern + decimal column names/types
- Handler layer: decimal arithmetic (.Sub/.Add) instead of int operators
- Models: deprecated amount_cents fields kept for SELECT * compatibility
- INSERT statements: old columns set to literal 0 for NOT NULL constraints

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

internal/ui/components/expense/expense.templ

@@ -14,6 +14,7 @@ import (
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/paymentmethod"
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/radio"
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/tagcombobox"
+	"github.com/shopspring/decimal"
 )
 
 type AddExpenseFormProps struct {
@@ -215,7 +216,7 @@ templ EditExpenseForm(spaceID string, exp *model.ExpenseWithTagsAndMethod, metho
 				Name:       "amount",
 				ID:         "edit-amount-" + exp.ID,
 				Type:       "number",
-				Value:      fmt.Sprintf("%.2f", float64(exp.AmountCents)/100.0),
+				Value:      model.FormatDecimal(exp.Amount),
 				Attributes: templ.Attributes{"step": "0.01", "required": "true"},
 			})
 		</div>
@@ -345,7 +346,7 @@ templ ItemSelectorSection(listsWithItems []model.ListWithUncheckedItems, oob boo
 	</div>
 }
 
-templ BalanceCard(spaceID string, balance int, allocated int, oob bool) {
+templ BalanceCard(spaceID string, balance decimal.Decimal, allocated decimal.Decimal, oob bool) {
 	<div
 		id="balance-card"
 		class="border rounded-lg p-4 bg-card text-card-foreground"
@@ -354,11 +355,11 @@ templ BalanceCard(spaceID string, balance int, allocated int, oob bool) {
 		}
 	>
 		<h2 class="text-lg font-semibold">Current Balance</h2>
-		<p class={ "text-3xl font-bold", templ.KV("text-destructive", balance < 0) }>
-			{ fmt.Sprintf("$%.2f", float64(balance)/100.0) }
-			if allocated > 0 {
+		<p class={ "text-3xl font-bold", templ.KV("text-destructive", balance.LessThan(decimal.Zero)) }>
+			{ model.FormatMoney(balance) }
+			if allocated.GreaterThan(decimal.Zero) {
 				<span class="text-base font-normal text-muted-foreground">
-					({ fmt.Sprintf("$%.2f", float64(allocated)/100.0) } in accounts)
+					({ model.FormatMoney(allocated) } in accounts)
 				</span>
 			}
 		</p>

internal/ui/components/moneyaccount/moneyaccount.templ

@@ -11,9 +11,10 @@ import (
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/input"
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/label"
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/pagination"
+	"github.com/shopspring/decimal"
 )
 
-templ BalanceSummaryCard(spaceID string, totalBalance int, availableBalance int, oob bool) {
+templ BalanceSummaryCard(spaceID string, totalBalance decimal.Decimal, availableBalance decimal.Decimal, oob bool) {
 	<div
 		id="accounts-balance-summary"
 		class="border rounded-lg p-4 bg-card text-card-foreground"
@@ -25,20 +26,20 @@ templ BalanceSummaryCard(spaceID string, totalBalance int, availableBalance int,
 		<div class="grid grid-cols-3 gap-4">
 			<div>
 				<p class="text-sm text-muted-foreground">Total Balance</p>
-				<p class={ "text-xl font-bold", templ.KV("text-destructive", totalBalance < 0) }>
-					{ fmt.Sprintf("$%.2f", float64(totalBalance)/100.0) }
+				<p class={ "text-xl font-bold", templ.KV("text-destructive", totalBalance.LessThan(decimal.Zero)) }>
+					{ model.FormatMoney(totalBalance) }
 				</p>
 			</div>
 			<div>
 				<p class="text-sm text-muted-foreground">Allocated</p>
 				<p class="text-xl font-bold">
-					{ fmt.Sprintf("$%.2f", float64(totalBalance-availableBalance)/100.0) }
+					{ model.FormatMoney(totalBalance.Sub(availableBalance)) }
 				</p>
 			</div>
 			<div>
 				<p class="text-sm text-muted-foreground">Available</p>
-				<p class={ "text-xl font-bold", templ.KV("text-destructive", availableBalance < 0) }>
-					{ fmt.Sprintf("$%.2f", float64(availableBalance)/100.0) }
+				<p class={ "text-xl font-bold", templ.KV("text-destructive", availableBalance.LessThan(decimal.Zero)) }>
+					{ model.FormatMoney(availableBalance) }
 				</p>
 			</div>
 		</div>
@@ -60,8 +61,8 @@ templ AccountCard(spaceID string, acct *model.MoneyAccountWithBalance, oob ...bo
 		<div class="flex justify-between items-start mb-3">
 			<div>
 				<h3 class="font-semibold text-lg">{ acct.Name }</h3>
-				<p class={ "text-2xl font-bold", templ.KV("text-destructive", acct.BalanceCents < 0) }>
-					{ fmt.Sprintf("$%.2f", float64(acct.BalanceCents)/100.0) }
+				<p class={ "text-2xl font-bold", templ.KV("text-destructive", acct.Balance.LessThan(decimal.Zero)) }>
+					{ model.FormatMoney(acct.Balance) }
 				</p>
 			</div>
 			<div class="flex gap-1">
@@ -359,11 +360,11 @@ templ TransferHistoryItem(spaceID string, t *model.AccountTransferWithAccount) {
 		<div class="flex items-center gap-2">
 			if t.Direction == model.TransferDirectionDeposit {
 				<span class="font-bold text-green-600 whitespace-nowrap">
-					+{ fmt.Sprintf("$%.2f", float64(t.AmountCents)/100.0) }
+					+{ model.FormatMoney(t.Amount) }
 				</span>
 			} else {
 				<span class="font-bold text-destructive whitespace-nowrap">
-					-{ fmt.Sprintf("$%.2f", float64(t.AmountCents)/100.0) }
+					-{ model.FormatMoney(t.Amount) }
 				</span>
 			}
 			@button.Button(button.Props{
@@ -382,4 +383,3 @@ templ TransferHistoryItem(spaceID string, t *model.AccountTransferWithAccount) {
 		</div>
 	</div>
 }
-

internal/ui/components/recurring/recurring.templ

@@ -73,11 +73,11 @@ templ RecurringItem(spaceID string, re *model.RecurringExpenseWithTagsAndMethod,
 		<div class="flex items-center gap-1 shrink-0">
 			if re.Type == model.ExpenseTypeExpense {
 				<p class="font-bold text-destructive">
-					- { fmt.Sprintf("$%.2f", float64(re.AmountCents)/100.0) }
+					- { model.FormatMoney(re.Amount) }
 				</p>
 			} else {
 				<p class="font-bold text-green-500">
-					+ { fmt.Sprintf("$%.2f", float64(re.AmountCents)/100.0) }
+					+ { model.FormatMoney(re.Amount) }
 				</p>
 			}
 			// Toggle pause/resume
@@ -352,7 +352,7 @@ templ EditRecurringForm(spaceID string, re *model.RecurringExpenseWithTagsAndMet
 				Name:       "amount",
 				ID:         "edit-recurring-amount-" + re.ID,
 				Type:       "number",
-				Value:      fmt.Sprintf("%.2f", float64(re.AmountCents)/100.0),
+				Value:      model.FormatDecimal(re.Amount),
 				Attributes: templ.Attributes{"step": "0.01", "required": "true"},
 			})
 		</div>