Include investment holding values in net worth and account balances

- Net worth report, balance sheet, and daily snapshots now add holding
  market values (falling back to cost basis) to investment-type account
  balances (investment, pension, stocks_shares_isa, crypto_wallet)
- Accounts list shows total value for investment accounts with a
  breakdown line ("£X cash + £Y holdings") when both are non-zero
- Add Holding modal gains a "Debit account for this purchase" toggle
  that creates a matching withdrawal transaction, enabling proper cash
  flow tracking for users who fund their brokerage via transfer first
- Both simple (holdings-only) and full cash-flow workflows produce
  correct net worth figures without double-counting

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

frontend/src/pages/accounts/AccountList.tsx

@@ -2,6 +2,7 @@ import { useState } from "react";
 import { Link } from "react-router-dom";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { getAccounts, createAccount, updateAccount, deleteAccount, getNetWorth, type Account } from "@/api/accounts";
+import { getPortfolio } from "@/api/investments";
 import { formatCurrency } from "@/utils/currency";
 import { cn } from "@/utils/cn";
 import {
@@ -57,6 +58,17 @@ export default function AccountList() {
     queryFn: getNetWorth,
   });
 
+  const { data: portfolio } = useQuery({
+    queryKey: ["portfolio"],
+    queryFn: getPortfolio,
+  });
+
+  const holdingValueByAccount = (portfolio?.holdings ?? []).reduce<Record<string, number>>((acc, h) => {
+    const v = Number(h.current_value || h.cost_basis_total);
+    acc[h.account_id] = (acc[h.account_id] ?? 0) + v;
+    return acc;
+  }, {});
+
   const invalidate = () => {
     qc.invalidateQueries({ queryKey: ["accounts"] });
     qc.invalidateQueries({ queryKey: ["net-worth"] });
@@ -129,6 +141,7 @@ export default function AccountList() {
           accounts={assets}
           onEdit={setEditing}
           onDelete={id => deleteMutation.mutate(id)}
+          holdingValueByAccount={holdingValueByAccount}
         />
       )}
 
@@ -147,6 +160,7 @@ export default function AccountList() {
           accounts={inactive}
           onEdit={setEditing}
           onDelete={id => deleteMutation.mutate(id)}
+          holdingValueByAccount={holdingValueByAccount}
           muted
         />
       )}
@@ -179,17 +193,21 @@ export default function AccountList() {
   );
 }
 
+const INVESTMENT_TYPES = new Set(["investment", "pension", "stocks_shares_isa", "crypto_wallet"]);
+
 function AccountGroup({
   title,
   accounts,
   onEdit,
   onDelete,
+  holdingValueByAccount = {},
   muted = false,
 }: {
   title: string;
   accounts: Account[];
   onEdit: (a: Account) => void;
   onDelete: (id: string) => void;
+  holdingValueByAccount?: Record<string, number>;
   muted?: boolean;
 }) {
   return (
@@ -243,14 +261,31 @@ function AccountGroup({
                 </div>
 
                 <div className="text-right shrink-0">
-                  <p className={cn("font-semibold tabular-nums", isLiability ? "text-destructive" : "text-foreground")}>
-                    {formatCurrency(account.current_balance, account.currency)}
-                  </p>
-                  {account.credit_limit != null && (
-                    <p className="text-xs text-muted-foreground">
-                      limit {formatCurrency(account.credit_limit, account.currency)}
-                    </p>
-                  )}
+                  {(() => {
+                    const holdingVal = INVESTMENT_TYPES.has(account.type) ? (holdingValueByAccount[account.id] ?? 0) : 0;
+                    const cashBal = Number(account.current_balance);
+                    const total = cashBal + holdingVal;
+                    return (
+                      <>
+                        <p className={cn("font-semibold tabular-nums", isLiability ? "text-destructive" : "text-foreground")}>
+                          {formatCurrency(holdingVal > 0 ? total : cashBal, account.currency)}
+                        </p>
+                        {holdingVal > 0 && cashBal !== 0 && (
+                          <p className="text-xs text-muted-foreground">
+                            {formatCurrency(cashBal, account.currency)} cash + {formatCurrency(holdingVal, account.currency)} holdings
+                          </p>
+                        )}
+                        {holdingVal > 0 && cashBal === 0 && (
+                          <p className="text-xs text-muted-foreground">holdings value</p>
+                        )}
+                        {account.credit_limit != null && (
+                          <p className="text-xs text-muted-foreground">
+                            limit {formatCurrency(account.credit_limit, account.currency)}
+                          </p>
+                        )}
+                      </>
+                    );
+                  })()}
                 </div>
 
                 <div className="flex items-center gap-1 opacity-100 sm:opacity-0 sm:group-hover:opacity-100 transition-opacity shrink-0">

frontend/src/pages/investments/AddHoldingModal.tsx

@@ -1,6 +1,7 @@
 import { useState, useEffect } from "react";
 import { X, Search, Loader2 } from "lucide-react";
 import { searchAssets, createHolding, addInvestmentTransaction, AssetSearchResult } from "@/api/investments";
+import { createTransaction } from "@/api/transactions";
 import { useUiStore } from "@/store/uiStore";
 import { format } from "date-fns";
 
@@ -28,6 +29,7 @@ export default function AddHoldingModal({ accounts, onClose, onSuccess }: Props)
   );
 
   const [priceMode, setPriceMode] = useState<"per_share" | "total">("per_share");
+  const [recordCash, setRecordCash] = useState(false);
   const [form, setForm] = useState({
     account_id: investAccounts[0]?.id ?? "",
     quantity: "",
@@ -76,6 +78,18 @@ export default function AddHoldingModal({ accounts, onClose, onSuccess }: Props)
         currency: form.currency,
         date: form.date,
       });
+      if (recordCash) {
+        const totalSpent = qty * price + (parseFloat(form.fees) || 0);
+        await createTransaction({
+          account_id: form.account_id,
+          type: "investment",
+          amount: -totalSpent,
+          currency: form.currency,
+          date: form.date,
+          description: `Buy ${selected.symbol} × ${qty}`,
+          status: "cleared",
+        });
+      }
       onSuccess();
     } catch (e: any) {
       const detail = e?.response?.data?.detail;
@@ -237,6 +251,25 @@ export default function AddHoldingModal({ accounts, onClose, onSuccess }: Props)
             />
           </div>
 
+          {/* Cash purchase toggle */}
+          <label className="flex items-start gap-3 cursor-pointer select-none p-3 rounded-lg border border-border hover:bg-secondary/40 transition-colors">
+            <div className="relative mt-0.5 shrink-0">
+              <input
+                type="checkbox"
+                checked={recordCash}
+                onChange={(e) => setRecordCash(e.target.checked)}
+                className="sr-only"
+              />
+              <div className={`w-9 h-5 rounded-full transition-colors ${recordCash ? "bg-primary" : "bg-secondary border border-input"}`}>
+                <div className={`w-3.5 h-3.5 rounded-full bg-white shadow transition-transform mt-0.5 ${recordCash ? "translate-x-4.5 ml-0.5" : "translate-x-0.5 ml-0.5"}`} />
+              </div>
+            </div>
+            <div>
+              <p className="text-sm font-medium">Debit account for this purchase</p>
+              <p className="text-xs text-muted-foreground mt-0.5">Records a matching withdrawal from the account. Enable this if you transferred cash to this account first and want to track the balance accurately.</p>
+            </div>
+          </label>
+
           {error && <p className="text-destructive text-sm bg-destructive/10 rounded-md px-3 py-2">{error}</p>}
 
           <div className="flex gap-3 pt-1">