feat: show Jobs tab for all vendors when no filter selected

- Add /admin/letzshop/jobs API endpoint for all jobs across vendors
- Update list_letzshop_jobs service to support optional vendor_id
- Remove x-if condition from Jobs tab button and panel
- Update JS to use global or vendor-specific endpoint based on selection
- Update jobs table subtitle to show context

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/templates/admin/marketplace-letzshop.html

@@ -125,9 +125,7 @@
         {{ tab_button('products', 'Products', tab_var='activeTab', icon='cube') }}
         {{ tab_button('orders', 'Orders', tab_var='activeTab', icon='shopping-cart', count_var='orderStats.pending') }}
         {{ tab_button('exceptions', 'Exceptions', tab_var='activeTab', icon='exclamation-circle', count_var='exceptionStats.pending') }}
-        <template x-if="selectedVendor">
-            <span>{{ tab_button('jobs', 'Jobs', tab_var='activeTab', icon='collection') }}</span>
-        </template>
+        {{ tab_button('jobs', 'Jobs', tab_var='activeTab', icon='collection') }}
         <template x-if="selectedVendor">
             <span>{{ tab_button('settings', 'Settings', tab_var='activeTab', icon='cog') }}</span>
         </template>
@@ -155,12 +153,10 @@
         {% include 'admin/partials/letzshop-exceptions-tab.html' %}
     {{ endtab_panel() }}
 
-    <!-- Jobs Tab - Vendor only -->
-    <template x-if="selectedVendor">
-        {{ tab_panel('jobs', tab_var='activeTab') }}
-            {% include 'admin/partials/letzshop-jobs-table.html' %}
-        {{ endtab_panel() }}
-    </template>
+    <!-- Jobs Tab -->
+    {{ tab_panel('jobs', tab_var='activeTab') }}
+        {% include 'admin/partials/letzshop-jobs-table.html' %}
+    {{ endtab_panel() }}
 </div>
 
 <!-- Tracking Modal -->

app/templates/admin/partials/letzshop-jobs-table.html

@@ -6,7 +6,10 @@
         <div class="flex items-center justify-between mb-4">
             <div>
                 <h3 class="text-lg font-semibold text-gray-700 dark:text-gray-200">Recent Jobs</h3>
-                <p class="text-sm text-gray-500 dark:text-gray-400">Product imports, exports, and order sync history</p>
+                <p class="text-sm text-gray-500 dark:text-gray-400">
+                    <span x-show="selectedVendor">Product imports, exports, and order sync history</span>
+                    <span x-show="!selectedVendor">All Letzshop jobs across all vendors</span>
+                </p>
             </div>
             <button
                 @click="loadJobs()"