Hide system equity accounts from Accounts page

System accounts (Operating Fund Balance, Reserve Fund Balance) are auto-created
as double-entry offsets when users set initial balances. They don't represent
real bank accounts and were confusing to see alongside actual accounts. Now
filtered from account lists, tab counts, and summary card totals. They remain
active under the covers for journal entries and are still visible on the
Balance Sheet report where equity belongs.

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

frontend/src/pages/accounts/AccountsPage.tsx

@@ -388,7 +388,9 @@ export function AccountsPage() {
   };
 
   // ── Filtering ──
+  // Hide system accounts (auto-created equity offsets) from the accounts view
   const filtered = accounts.filter((a) => {
+    if (a.is_system) return false;
     if (search && !a.name.toLowerCase().includes(search.toLowerCase()) && !String(a.account_number).includes(search)) return false;
     if (filterType && a.account_type !== filterType) return false;
     if (filterFund && a.fund_type !== filterFund) return false;
@@ -403,9 +405,10 @@ export function AccountsPage() {
   const reserveInvestments = investments.filter((i) => i.fund_type === 'reserve' && i.is_active);
 
   // ── Summary cards ──
+  // Exclude system accounts from summaries to avoid double-counting
   const totalsByType = accounts.reduce(
     (acc, a) => {
-      if (a.is_active) {
+      if (a.is_active && !a.is_system) {
         acc[a.account_type] = (acc[a.account_type] || 0) + parseFloat(a.balance || '0');
       }
       return acc;