feat(prospecting): add delete button to prospects list

- Trash icon button in Actions column with confirmation dialog
- Calls DELETE /admin/prospecting/prospects/{id} (existing endpoint)
- Reloads list after successful deletion
- Toast notification on success/failure

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/modules/prospecting/templates/prospecting/admin/prospects.html

@@ -132,6 +132,11 @@
                                title="View details">
                                 <span x-html="$icon('eye', 'w-5 h-5')"></span>
                             </a>
+                            <button type="button" @click="deleteProspect(p)"
+                                    class="flex items-center justify-center p-2 text-red-600 rounded-lg hover:bg-red-50 dark:text-red-400 dark:hover:bg-gray-700 focus:outline-none transition-colors"
+                                    title="Delete">
+                                <span x-html="$icon('trash', 'w-5 h-5')"></span>
+                            </button>
                         </div>
                     </td>
                 </tr>