Make mobile account surfaces readable

Mobile review found that account payment rows could collapse labels vertically and several secondary links had small touch targets on narrow phones. The patch keeps the existing visual system but allows account rows to stack on mobile, improves tap height, and tightens the Scan Terminal narrow-screen container.

Constraint: Must keep the current desktop layout and avoid adding dependencies

Rejected: Rebuild the account page layout wholesale | too broad for a targeted mobile audit

Confidence: high

Scope-risk: narrow

Directive: Keep long account/payment identifiers breakable on narrow screens

Tested: iPhone SE and iPhone 12 Playwright mobile audits show no horizontal overflow on checked pages

Tested: npx tsc --noEmit --pretty false --project frontend/tsconfig.json

Tested: npm run build

Tested: npm run test:business

Not-tested: Authenticated /ops data state because local Supabase/admin gating redirects to the public shell

frontend/components/dashboard/ScanTerminalMobile.module.css

@@ -491,14 +491,26 @@
 
 @media (max-width: 520px) {
   .root :global(.scan-terminal) {
+    box-sizing: border-box;
+    max-width: 100vw;
+    overflow-x: clip;
     padding: 6px;
   }
 
   .root :global(.scan-data-grid) {
+    box-sizing: border-box;
+    min-width: 0;
+    width: 100%;
+    max-width: 100%;
     padding: 10px;
     border-radius: 16px;
   }
 
+  .root :global(.scan-topbar-tabs) {
+    max-width: 100%;
+    gap: 8px;
+  }
+
   .root :global(.scan-upgrade-announcement) {
     margin: -2px 0 2px;
     padding: 12px;