feat: add export/import buttons to tickets UI

corvid/templates/tickets_base.html

@@ -282,6 +282,11 @@ textarea.desc-input {
     <div class="search-wrap">
       <input type="search" id="search-input" placeholder="Search tickets…" autocomplete="off" title="Search title & description (/)">
     </div>
+    <button class="btn btn-subtle btn-sm" onclick="exportTickets(); event.stopPropagation()">Export</button>
+    <label class="btn btn-subtle btn-sm" style="cursor:pointer" title="Import tickets from JSON">
+      Import
+      <input type="file" accept=".json,application/json" onchange="importTickets(event)" style="display:none">
+    </label>
     <button class="btn btn-primary btn-sm" onclick="openCreate(); event.stopPropagation()">+ New Ticket</button>
   </div>
 </div>
@@ -1186,6 +1191,43 @@ document.getElementById('env-create-overlay').addEventListener('click', e => {
 document.addEventListener('click', () => closeEnvDropdown());
 document.getElementById('env-selector').addEventListener('click', e => e.stopPropagation());
 
+// ── Export / Import ──────────────────────────────────────────────────────────
+
+async function exportTickets() {
+  try {
+    const data = await api('/api/tickets/export');
+    const blob = new Blob([JSON.stringify(data, null, 2)], {type: 'application/json'});
+    const url = URL.createObjectURL(blob);
+    const a = document.createElement('a');
+    const ts = new Date().toISOString().slice(0, 10);
+    a.href = url;
+    a.download = `tickets-export-${ts}.json`;
+    a.click();
+    URL.revokeObjectURL(url);
+  } catch(e) {
+    toast(e.message, true);
+  }
+}
+
+async function importTickets(event) {
+  const file = event.target.files?.[0];
+  if (!file) return;
+  event.target.value = '';
+  try {
+    const text = await file.text();
+    const body = JSON.parse(text);
+    const result = await api('/api/tickets/import', {
+      method: 'POST',
+      headers: {'Content-Type': 'application/json'},
+      body: JSON.stringify(body),
+    });
+    toast(`Imported ${result.imported} ticket(s)`);
+    await loadEnvironments();
+  } catch(e) {
+    toast(e.message || 'Import failed', true);
+  }
+}
+
 loadEnvironments();
 </script>
 {% endblock %}