Accounting: Sales Receipts, COA sync to dashboard, vendor-expense recognition

- Add Sales Receipts page (dashboard/accounting/sales-receipts): records a
  cash sale (name, address, income account, price, qty) — deposits and books
  income in one step via a transaction. New accounting.sales_receipts table.
- Sync chart of accounts to the accounting dashboard: mirror accounting.accounts
  into public.chart_of_accounts for platform associations (one-way, same id) so
  Bill Approvals and every COA consumer use the dashboard's accounts. Legacy
  rows hidden; Bill Approvals made system-aware.
- Vendor-expense recognition: a vendor payment with no bill now books the
  expense directly (Dr Expense / Cr Bank) on the payment date instead of going
  to A/P; payments against open bills still clear A/P (applied FIFO). Backfill
  reclassifies unbilled payments stuck in A/P. Expense Summary report made
  GL-driven so it follows the same rule.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

supabase/migrations/20260603184745_create_sales_receipts.sql

@@ -0,0 +1,37 @@
+create table if not exists accounting.sales_receipts (
+  id uuid primary key default gen_random_uuid(),
+  company_id uuid not null references accounting.companies(id) on delete cascade,
+  number text not null,
+  receipt_date date not null default current_date,
+  customer_name text,
+  customer_address text,
+  income_account_id uuid references accounting.accounts(id),
+  deposit_account_id uuid references accounting.accounts(id),
+  quantity numeric not null default 1,
+  rate numeric not null default 0,
+  total numeric not null default 0,
+  memo text,
+  transaction_id uuid references accounting.transactions(id) on delete set null,
+  created_at timestamptz not null default now(),
+  updated_at timestamptz not null default now()
+);
+
+create index if not exists idx_sales_receipts_company on accounting.sales_receipts(company_id);
+create index if not exists idx_sales_receipts_txn on accounting.sales_receipts(transaction_id);
+
+alter table accounting.sales_receipts enable row level security;
+
+create policy "Accounting staff full access" on accounting.sales_receipts
+  for all using (accounting.is_accounting_staff()) with check (accounting.is_accounting_staff());
+create policy "Members CRUD sales_receipts" on accounting.sales_receipts
+  for all using (accounting.is_company_member(company_id, auth.uid()))
+  with check (accounting.is_company_member(company_id, auth.uid()));
+create policy "Board view sales_receipts" on accounting.sales_receipts
+  for select using (accounting.is_company_board_member(company_id));
+
+create trigger trg_sales_receipts_updated
+  before update on accounting.sales_receipts
+  for each row execute function public.update_updated_at_column();
+
+grant select, insert, update, delete on accounting.sales_receipts to authenticated;
+grant all on accounting.sales_receipts to service_role;