feat(frontend): workday summary modal, print analytics UI, staff zone-PIN management, report upgrades

manager_dashboard:
- DashboardPage: WorkdaySummaryModal integration (view / close-day flows); revenue chart upgrades
- WorkdaySummaryModal: new component — shows full shift/revenue summary before closing the day
- StaffTab: full rewrite — zone-assignment modal, reset-PIN modal, actions dropdown, richer staff card
- ProductsTab: digital-menu fields surfaced in product form
- PrintFontsTab: expanded font-size/weight controls per printer channel
- TablesConfigTab / TablesPage / tableColourStore: color picker and zone fields for tables
- FilterBar: unified filter component with date-range, printer, and category selectors
- CategoryPerformance / ProductPerformance / TableAnalytics: donut/bar charts,
  thermal+browser print modals, richer breakdown tables
- PrinterHistory: redesigned with per-printer drill-down and summary blocks
- TrafficAnalytics / WorkDaySummary / RevenueTrends / ShiftsOverview / StaffLeaderboard: polish pass
- tokens.js: design token updates

waiter_pwa:
- TableCard: show table color indicator from zone/colour config

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

manager_dashboard/src/pages/reports/restaurant/WorkDaySummary.jsx

@@ -13,7 +13,7 @@ import DeleteConfirmModal from '../../../ui/DeleteConfirmModal'
 import EmptyState from '../shared/EmptyState'
 import SkeletonTable from '../shared/SkeletonTable'
 import ExportButton from '../shared/ExportButton'
-import { fmtEUR, fmtNum, fmtDate, fmtTime, fmtDuration, fmtDateTime } from '../shared/reportDesignTokens'
+import { fmtEUR, fmtNum, fmtDate, fmtTime, fmtDuration, fmtDateTime, fmtDateStr } from '../shared/reportDesignTokens'
 
 function today() { return new Date().toISOString().slice(0, 10) }
 function monthAgo() { const d = new Date(); d.setDate(d.getDate() - 30); return d.toISOString().slice(0, 10) }
@@ -228,7 +228,7 @@ export default function WorkDaySummary() {
 
       <div className="flex-1 overflow-y-auto p-6">
         {chartData.length > 0 && (
-          <Panel title="Έσοδα ανά Εργάσιμη Μέρα" subtitle={`${days.length} μέρες · ${from} → ${to}`}>
+          <Panel title="Έσοδα ανά Εργάσιμη Μέρα" subtitle={`${days.length} μέρες · ${fmtDateStr(from)} → ${fmtDateStr(to)}`}>
             <div style={{ height: 220 }}>
               <ResponsiveContainer width="100%" height="100%">
                 <LineChart data={chartData} margin={{ top: 8, right: 16, bottom: 4, left: 4 }}>