fix(admin): shorten the receipt letter, show the account id

The receipt letter repeated what the receipt itself states. It now carries the
amount, the moment of payment with its offset, and the link — the receipt is
the document, and it opens without authentication, so there is nothing for the
two to disagree about. Subject reworded to name what it is.

The ledger and tax-export tables labelled the account link "card", meaning the
user card. On pages about payments that reads as a bank card, which is exactly
how it was misread. Both now show the first eight characters of the account id,
so the column carries data — two rows from the same buyer are visible at a
glance — while the link still holds the whole id.

backend/internal/server/handlers_admin_console.go

@@ -1375,6 +1375,17 @@ func normalizeComplaintStatus(s string) string {
 	return ""
 }
 
+// shortID abbreviates an account id for a table cell: enough to recognise the same buyer across
+// rows at a glance, while the link still carries the whole id. Money tables have no room for a full
+// uuid, and a generic label there ("card") read as a payment card on the very pages about payments.
+func shortID(id string) string {
+	const n = 8
+	if len(id) <= n {
+		return id
+	}
+	return id[:n]
+}
+
 // fmtTime formats a timestamp for display, or "" when zero.
 func fmtTime(t time.Time) string {
 	if t.IsZero() {

backend/internal/server/handlers_admin_ledger.go

@@ -130,17 +130,18 @@ func (s *Server) consoleLedger(c *gin.Context) {
 // the template — only a funded order can be reversed.
 func ledgerRow(r payments.LedgerReportRow) adminconsole.LedgerRow {
 	row := adminconsole.LedgerRow{
-		At:         fmtTime(r.CreatedAt),
-		AccountID:  r.AccountID.String(),
-		Kind:       r.Kind,
-		Source:     r.Source,
-		Origin:     r.Origin,
-		ChipsDelta: r.ChipsDelta,
-		Order:      r.OrderID,
-		Provider:   r.Provider,
-		Shop:       r.Shop,
-		Refundable: r.Kind == "fund" && r.OrderID != "",
-		Title:      snapshotTitle(r.Snapshot),
+		At:           fmtTime(r.CreatedAt),
+		AccountID:    r.AccountID.String(),
+		AccountShort: shortID(r.AccountID.String()),
+		Kind:         r.Kind,
+		Source:       r.Source,
+		Origin:       r.Origin,
+		ChipsDelta:   r.ChipsDelta,
+		Order:        r.OrderID,
+		Provider:     r.Provider,
+		Shop:         r.Shop,
+		Refundable:   r.Kind == "fund" && r.OrderID != "",
+		Title:        snapshotTitle(r.Snapshot),
 	}
 	if r.HasMoney() {
 		row.Money = fmtMoney(r.Money)

backend/internal/server/handlers_admin_mynalog.go

@@ -59,10 +59,11 @@ func (s *Server) consoleMyNalog(c *gin.Context) {
 	}
 	for _, cn := range queue.Cancels {
 		view.Cancels = append(view.Cancels, adminconsole.MyNalogCancelRow{
-			LedgerID:    cn.LedgerID.String(),
-			AccountID:   cn.AccountID.String(),
-			ReceiptUUID: cn.ReceiptUUID,
-			Failed:      cn.CancelStatus == payments.MyNalogCancelFailed,
+			LedgerID:     cn.LedgerID.String(),
+			AccountID:    cn.AccountID.String(),
+			AccountShort: shortID(cn.AccountID.String()),
+			ReceiptUUID:  cn.ReceiptUUID,
+			Failed:       cn.CancelStatus == payments.MyNalogCancelFailed,
 		})
 	}
 
@@ -97,15 +98,16 @@ func fmtMinor(minor int64, cur payments.Currency) string {
 // the tax service has issued one.
 func (s *Server) myNalogRow(in payments.MyNalogIncome, inn string, loc *time.Location) adminconsole.MyNalogRow {
 	row := adminconsole.MyNalogRow{
-		LedgerID:    in.LedgerID.String(),
-		AccountID:   in.AccountID.String(),
-		At:          in.OperationTime.In(loc).Format("2006-01-02 15:04"),
-		Amount:      in.Amount.String(),
-		Name:        s.mynalog.ReceiptName(in),
-		Status:      in.Status,
-		Attempts:    in.Attempts,
-		LastError:   in.LastError,
-		ReceiptUUID: in.ReceiptUUID,
+		LedgerID:     in.LedgerID.String(),
+		AccountID:    in.AccountID.String(),
+		AccountShort: shortID(in.AccountID.String()),
+		At:           in.OperationTime.In(loc).Format("2006-01-02 15:04"),
+		Amount:       in.Amount.String(),
+		Name:         s.mynalog.ReceiptName(in),
+		Status:       in.Status,
+		Attempts:     in.Attempts,
+		LastError:    in.LastError,
+		ReceiptUUID:  in.ReceiptUUID,
 	}
 	if in.ReceiptUUID != "" && inn != "" {
 		row.ReceiptURL = s.mynalog.ReceiptURL(inn, in.ReceiptUUID)