Add ticket status setter and prevent draft text loss

- Set ticket state (Offen / In Bearbeitung / Warten auf Schließen /
  Geschlossen) from the ticket detail page via a live PUT to Zammad;
  pending-close gets a default pending time and the change is synced back
  so it isn't flagged as an external change
- Replace the disruptive meta-refresh with a JS auto-refresh that pauses
  while a text field has unsent content or focus
- Persist reply/new-ticket drafts to localStorage and restore them after
  a reload or accidental navigation

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/zammad.py

@@ -126,24 +126,41 @@ class ZammadClient:
         r = self.session.get(f"{self.base}/api/v1/signshow", timeout=30)
         return r.headers.get("CSRF-TOKEN")
 
-    def _post(self, path: str, payload: dict, _retry: bool = True):
+    def _write(self, method: str, path: str, payload: dict, _retry: bool = True):
         self.ensure_auth()
         headers = {}
         if not config.ZAMMAD_TOKEN:
             csrf = self._csrf()
             if csrf:
                 headers["X-CSRF-Token"] = csrf
-        r = self.session.post(f"{self.base}{path}", json=payload,
-                              headers=headers, timeout=60)
+        r = self.session.request(method, f"{self.base}{path}", json=payload,
+                                 headers=headers, timeout=60)
         if r.status_code in (401, 403) and _retry and not config.ZAMMAD_TOKEN:
             log.warning("Auth/CSRF abgelaufen (HTTP %s), erneuter Login.", r.status_code)
             self._authed = False
             self._login_session()
-            return self._post(path, payload, _retry=False)
+            return self._write(method, path, payload, _retry=False)
         if r.status_code not in (200, 201):
-            raise ZammadError(f"POST {path} -> HTTP {r.status_code}: {r.text[:300]}")
+            raise ZammadError(f"{method} {path} -> HTTP {r.status_code}: {r.text[:300]}")
         return r.json()
 
+    def _post(self, path: str, payload: dict, _retry: bool = True):
+        return self._write("POST", path, payload, _retry)
+
+    def _put(self, path: str, payload: dict, _retry: bool = True):
+        return self._write("PUT", path, payload, _retry)
+
+    def ticket_states(self) -> list[dict]:
+        return self._get("/api/v1/ticket_states")
+
+    def set_state(self, ticket_id: int, state_id: int,
+                  pending_time: str | None = None) -> dict:
+        """Status eines Tickets setzen (an EPI wirksam)."""
+        payload = {"state_id": state_id}
+        if pending_time:
+            payload["pending_time"] = pending_time
+        return self._put(f"/api/v1/tickets/{ticket_id}", payload)
+
     def create_article(self, ticket_id: int, body: str,
                        attachments: list[dict] | None = None) -> dict:
         """Antwort/Nachricht an ein bestehendes Ticket anhängen (an EPI sichtbar)."""