Fix account balances showing $0 and dashboard KPIs on new tenants

Root cause: multiple issues with balance computation across the system.

Accounts list:
- findAll() was doing SELECT * FROM accounts, returning the stale
  denormalized `balance` column (always 0). Now computes balances from
  journal entries using proper double-entry logic (debit-credit for
  assets/expenses, credit-debit for liabilities/equity/income).

Dashboard KPIs:
- Total Cash filtered by name LIKE '%Cash%' which missed accounts not
  named "Cash". Now queries ALL asset accounts regardless of name.
- Reserve Fund queried the legacy reserve_components.current_fund_balance
  column. Now computes from journal entries on reserve asset accounts.

Opening balance journal entries:
- On blank tenants, equity offset accounts (3000/3100) don't exist, so
  the balancing journal entry line was silently skipped, leaving entries
  unbalanced. Now auto-creates Operating Fund Balance (3000) and Reserve
  Fund Balance (3100) equity accounts when needed.

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

backend/src/modules/reports/reports.service.ts

@@ -394,28 +394,44 @@ export class ReportsService {
   }
 
   async getDashboardKPIs() {
-    // Total cash (all asset accounts with 'Cash' in name)
+    // Total cash: ALL asset accounts (not just those named "Cash")
+    // Uses proper double-entry balance: debit - credit for assets
     const cash = await this.tenant.query(`
       SELECT COALESCE(SUM(sub.balance), 0) as total FROM (
         SELECT COALESCE(SUM(jel.debit), 0) - COALESCE(SUM(jel.credit), 0) as balance
         FROM accounts a
         LEFT JOIN journal_entry_lines jel ON jel.account_id = a.id
         LEFT JOIN journal_entries je ON je.id = jel.journal_entry_id AND je.is_posted = true AND je.is_void = false
-        WHERE a.account_type = 'asset' AND a.name LIKE '%Cash%' AND a.is_active = true
+        WHERE a.account_type = 'asset' AND a.is_active = true
         GROUP BY a.id
       ) sub
     `);
     const totalCash = parseFloat(cash[0]?.total || '0');
 
-    // Receivables
+    // Receivables: sum of unpaid invoices
     const ar = await this.tenant.query(`
       SELECT COALESCE(SUM(amount - amount_paid), 0) as total
       FROM invoices WHERE status NOT IN ('paid', 'void', 'written_off')
     `);
 
-    // Reserve fund balance
+    // Reserve fund balance: computed from journal entries on reserve fund_type accounts
+    // credit - debit for equity/liability/income accounts (reserve equity + reserve income - reserve expenses)
     const reserves = await this.tenant.query(`
-      SELECT COALESCE(SUM(current_fund_balance), 0) as total FROM reserve_components
+      SELECT COALESCE(SUM(sub.balance), 0) as total FROM (
+        SELECT
+          CASE
+            WHEN a.account_type IN ('asset')
+              THEN COALESCE(SUM(jel.debit), 0) - COALESCE(SUM(jel.credit), 0)
+            WHEN a.account_type IN ('expense')
+              THEN -(COALESCE(SUM(jel.debit), 0) - COALESCE(SUM(jel.credit), 0))
+            ELSE COALESCE(SUM(jel.credit), 0) - COALESCE(SUM(jel.debit), 0)
+          END as balance
+        FROM accounts a
+        LEFT JOIN journal_entry_lines jel ON jel.account_id = a.id
+        LEFT JOIN journal_entries je ON je.id = jel.journal_entry_id AND je.is_posted = true AND je.is_void = false
+        WHERE a.fund_type = 'reserve' AND a.account_type IN ('asset') AND a.is_active = true
+        GROUP BY a.id, a.account_type
+      ) sub
     `);
 
     // Delinquent count (overdue invoices)
@@ -434,7 +450,7 @@ export class ReportsService {
     return {
       total_cash: totalCash.toFixed(2),
       total_receivables: ar[0]?.total || '0.00',
-      reserve_fund_balance: reserves[0]?.total || '0.00',
+      reserve_fund_balance: parseFloat(reserves[0]?.total || '0').toFixed(2),
       delinquent_units: parseInt(delinquent[0]?.count || '0'),
       recent_transactions: recentTx,
     };