feat: cashier/counter reports, service-order & remission flows, Rached migration utils

- Add "Mis cortes de caja" report for cashiers/counters with sales detail.
- Cash register history scoped to own cuts for non-admin roles; new /register/<id>/sales endpoint.
- Remove dashboard from cashier menu; add Reports to cashier/counter.
- Service orders: assign mechanic, budget field, invoice flag, counter/cashier can add items/remissions, convert to remission.
- Remission notes module (UI, CSS, courier, counter remissions).
- Customer hard-delete and vehicle/customer linkage in workshop.
- POS: always show search results, compact payment grid, credit validation, tier pricing (5%/10%), ticket with customer/folio.
- Inventory: CSV template with sku_secondary, alias import.
- Rached migration scripts and DB migrations.
- Version-bump cached JS/CSS query strings.

Excludes local Rached session tokens/captures (rached_*.json / rached_*.txt).

pos/templates/dashboard.html

@@ -158,6 +158,16 @@
           Ventas Históricas
         </a>
 
+        <a href="/pos/remission-notes" class="nav-link">
+          <span class="nav-link__icon">
+            <svg width="16" height="16" viewBox="0 0 16 16" fill="none" stroke="currentColor" stroke-width="1.5">
+              <path d="M2 3h12v10H2z"/>
+              <path d="M5 7h6M5 10h4" stroke-width="1.2"/>
+            </svg>
+          </span>
+          Notas de Remisión
+        </a>
+
         <div class="sidebar__section-label">Gestión</div>
 
         <a href="/pos/marketplace" class="nav-link">
@@ -595,15 +605,15 @@
 
 
   <script src="/pos/static/js/chart.umd.min.js" defer></script>
-  <script src="/pos/static/js/i18n.js?v=36" defer></script>
-  <script src="/pos/static/js/app-init.js?v=2" defer></script>
+  <script src="/pos/static/js/i18n.js?v=39" defer></script>
+  <script src="/pos/static/js/app-init.js?v=5" defer></script>
   <script src="/pos/static/js/splash-loader.js?v=33" defer></script>
   <script src="/pos/static/js/pos-utils.js?v=33" defer></script>
-  <script src="/pos/static/js/sidebar.js?v=36" defer></script>
+  <script src="/pos/static/js/sidebar.js?v=44" defer></script>
   <script src="/pos/static/js/dashboard-stats.js?v=33" defer></script>
   <script src="/pos/static/js/dashboard.js?v=33" defer></script>
   <script src="/pos/static/js/sync-engine.js" defer></script>
-  <script>if('serviceWorker' in navigator){navigator.serviceWorker.register('/pos/sw.js',{scope:'/pos/'});}</script>
+  <script>if('serviceWorker' in navigator){navigator.serviceWorker.register('/pos/sw.js?v=34',{scope:'/pos/'});}</script>
   <script src="/pos/static/js/pwa-install.js" defer></script>
 
   <script src="/pos/static/js/chat.js" defer></script>