Vest: an account's name ends in the number the Vest app shows

Vest's app shows attempt_index + 1 ("Account 73"), padded below 10
("Account 01"); the name ended in attempt_index, one lower, so the
dashboard's V50K-E-D3-T10-73 was Vest's Account 74. It now ends in the
app's number, and 0 for an account Vest gives no attempt index (its
"Legacy Account"). Account types match on the prefix, and everything saved
locally is keyed by account id, so nothing else moves.

Reports mark a Vest firm vestAppNumbers. The master (634d52f) renames what
it saved under the old numbers on the first such report from a person, and
from then on leaves out a Vest firm reported under the old ones.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lib/master-protocol.ts

@@ -159,6 +159,11 @@ export interface FirmStats {
     /** ISO time the firm's last good sync finished (statusVersion builds), sent
      *  once synced. The statuses count only while it is recent. Optional. */
     syncedAt?: string;
+    /** 1 on a Vest firm: its account names end in the number the Vest app
+     *  shows (Account 73 = V50K-E-D3-T10-73). Older builds' were one lower; on
+     *  the first report with this, the master renames what it saved under
+     *  those. */
+    vestAppNumbers?: 1;
     /** Per account type, summing to the firm's own totals. Optional so a master
      *  on an older build simply ignores it. */
     accountTypes?: AccountTypeStats[];