Track session standings so the dealer can settle up at the end of the night

The hand log answered "what happened in hand 12"; it couldn't answer "what
does Alice owe". Each resolved pot now records a per-seat ledger (what that
player put in, what they took down) alongside the payouts, and a Session
Standings panel sums it into one row per player — paid in, won, net, sorted
by who's up. The CSV export carries the same table, so one file covers both
the hand-by-hand trail and the cash-out numbers.

Keyed by seat id rather than name, so renaming or reseating a player doesn't
split their totals. Hands recorded before this change have no ledger and are
skipped rather than counted wrong.

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_015bnp7xKUPFFSpwkYNFaPgb

JoshHeaps.Net/wwwroot/js/casino/holdem/handHistoryExport.js

@@ -15,7 +15,7 @@ const HandHistoryExport = {
         }
     },
 
-    toCsv(handHistory) {
+    toCsv(handHistory, standings = []) {
         const rows = [["Hand #", "Time", "Pot", "Payouts"]];
         // handHistory is stored newest-first; the export reads better oldest-first.
         [...handHistory].reverse().forEach(entry => {
@@ -29,6 +29,18 @@ const HandHistoryExport = {
                 payouts,
             ]);
         });
+
+        // The settle-up numbers go in the same file as the hands they came from, so a
+        // dealer handing over one export isn't asked for a second one at cash-out.
+        if (standings.length > 0) {
+            rows.push([]);
+            rows.push(["Session Standings"]);
+            rows.push(["Player", "Paid In", "Won", "Net"]);
+            standings.forEach(row => {
+                rows.push([row.name, Money.format(row.in), Money.format(row.won), Money.formatSigned(row.net)]);
+            });
+        }
+
         return rows.map(row => row.map(f => this.csvField(f)).join(",")).join("\r\n");
     },
 
@@ -39,8 +51,8 @@ const HandHistoryExport = {
         return `holdem-hand-history-${stamp}.csv`;
     },
 
-    download(handHistory) {
-        const csv = this.toCsv(handHistory);
+    download(handHistory, standings = []) {
+        const csv = this.toCsv(handHistory, standings);
         const blob = new Blob([csv], { type: "text/csv;charset=utf-8;" });
         const url = URL.createObjectURL(blob);
         const link = document.createElement("a");