fix: IMAP-Konto bearbeiten + Löschen auch bei sync_running

- Store: UpdateCredentials() — Zugangsdaten + Passwort neu verschlüsseln,
  setzt status='idle', error_msg='', sync_running=false zurück
- Handler: PATCH /api/imap/{id} unterstützt nun Credential-Update
  (name/host/username vorhanden = Credential-Update, sonst sync_interval)
- Frontend: "Bearbeiten"-Button öffnet Edit-Dialog mit allen Feldern;
  Passwort-Feld leer = unverändertes Passwort
- Frontend: Löschen-Button nicht mehr durch sync_running blockiert
  (nur noch bei status=running gesperrt)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/api/import_handlers.go

@@ -273,7 +273,9 @@ func (s *Server) handleSyncNow(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusOK, acc)
 }
 
-// handleUpdateImapInterval updates the automatic sync interval for an IMAP account.
+// handleUpdateImapInterval updates the automatic sync interval or full credentials
+// of an IMAP account. When name/host/username are present the credentials are updated;
+// otherwise only sync_interval_min is changed.
 func (s *Server) handleUpdateImapInterval(w http.ResponseWriter, r *http.Request) {
 	if s.imapStore == nil {
 		writeError(w, http.StatusServiceUnavailable, "IMAP not configured")
@@ -300,12 +302,47 @@ func (s *Server) handleUpdateImapInterval(w http.ResponseWriter, r *http.Request
 
 	var req struct {
 		SyncIntervalMin int    `json:"sync_interval_min"`
+		Name            string `json:"name"`
+		Host            string `json:"host"`
+		Port            int    `json:"port"`
+		TLS             string `json:"tls"`
+		Username        string `json:"username"`
+		Password        string `json:"password"`
 	}
 	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
 		writeError(w, http.StatusBadRequest, "invalid request body")
 		return
 	}
 
+	// Credential update when name/host/username are provided.
+	if req.Name != "" || req.Host != "" || req.Username != "" {
+		if req.Name == "" || req.Host == "" || req.Username == "" {
+			writeError(w, http.StatusBadRequest, "name, host and username are required for credential update")
+			return
+		}
+		port := req.Port
+		if port == 0 {
+			port = acc.Port
+		}
+		tls := req.TLS
+		if tls == "" {
+			tls = acc.TLS
+		}
+		updated := imapstore.Account{Name: req.Name, Host: req.Host, Port: port, TLS: tls, Username: req.Username}
+		if err := s.imapStore.UpdateCredentials(r.Context(), id, updated, req.Password); err != nil {
+			writeError(w, http.StatusInternalServerError, "failed to update credentials")
+			return
+		}
+		acc, err = s.imapStore.Get(r.Context(), id)
+		if err != nil {
+			writeError(w, http.StatusInternalServerError, "failed to reload account")
+			return
+		}
+		writeJSON(w, http.StatusOK, acc)
+		return
+	}
+
+	// Sync interval update.
 	// 0 = disabled; otherwise must be between 5 and 1440 minutes.
 	if req.SyncIntervalMin != 0 && (req.SyncIntervalMin < 5 || req.SyncIntervalMin > 1440) {
 		writeError(w, http.StatusBadRequest, "sync_interval_min must be 0 (disabled) or between 5 and 1440")

internal/imap/store.go

@@ -282,6 +282,33 @@ func (s *Store) UpdateDone(ctx context.Context, id int64, count int) error {
 	return nil
 }
 
+// UpdateCredentials updates the connection details and optionally the password
+// of an IMAP account. Pass an empty password to leave it unchanged.
+func (s *Store) UpdateCredentials(ctx context.Context, id int64, acc Account, password string) error {
+	if password != "" {
+		enc, err := encryptPassword(password, s.encKey)
+		if err != nil {
+			return fmt.Errorf("imap store: encrypt password: %w", err)
+		}
+		_, err = s.pool.Exec(ctx,
+			`UPDATE imap_accounts SET name=$1, host=$2, port=$3, tls=$4, username=$5, password_enc=$6,
+			 status='idle', error_msg='', sync_running=false WHERE id=$7`,
+			acc.Name, acc.Host, acc.Port, acc.TLS, acc.Username, enc, id)
+		if err != nil {
+			return fmt.Errorf("imap store: update credentials: %w", err)
+		}
+	} else {
+		_, err := s.pool.Exec(ctx,
+			`UPDATE imap_accounts SET name=$1, host=$2, port=$3, tls=$4, username=$5,
+			 status='idle', error_msg='', sync_running=false WHERE id=$6`,
+			acc.Name, acc.Host, acc.Port, acc.TLS, acc.Username, id)
+		if err != nil {
+			return fmt.Errorf("imap store: update credentials (no pw): %w", err)
+		}
+	}
+	return nil
+}
+
 // UpdateSyncInterval sets the automatic sync interval for an account.
 // intervalMin == 0 disables automatic sync.
 func (s *Store) UpdateSyncInterval(ctx context.Context, id int64, intervalMin int) error {

src/app/imap/page.tsx

@@ -12,6 +12,7 @@ import {
   getImapProgress,
   triggerImapSync,
   updateImapInterval,
+  updateImapAccount,
   type ImapAccount,
   type ImapFolder,
 } from "@/lib/api";
@@ -50,6 +51,17 @@ export default function ImapPage() {
   const [dialogOpen, setDialogOpen] = useState(false);
   const [deleteConfirm, setDeleteConfirm] = useState<number | null>(null);
 
+  // Edit state
+  const [editAccount, setEditAccount] = useState<ImapAccount | null>(null);
+  const [editName, setEditName] = useState("");
+  const [editHost, setEditHost] = useState("");
+  const [editPort, setEditPort] = useState("993");
+  const [editTls, setEditTls] = useState("ssl");
+  const [editUsername, setEditUsername] = useState("");
+  const [editPassword, setEditPassword] = useState("");
+  const [editSaving, setEditSaving] = useState(false);
+  const [editError, setEditError] = useState("");
+
   // Form state
   const [formName, setFormName] = useState("");
   const [formHost, setFormHost] = useState("");
@@ -209,6 +221,43 @@ export default function ImapPage() {
     setDeleteConfirm(null);
   }
 
+  function openEdit(acc: ImapAccount) {
+    setEditAccount(acc);
+    setEditName(acc.name);
+    setEditHost(acc.host);
+    setEditPort(String(acc.port));
+    setEditTls(acc.tls);
+    setEditUsername(acc.username);
+    setEditPassword("");
+    setEditError("");
+  }
+
+  async function handleEditSave() {
+    if (!editAccount) return;
+    if (!editName || !editHost || !editUsername) {
+      setEditError("Name, Host und Benutzername sind Pflichtfelder.");
+      return;
+    }
+    setEditSaving(true);
+    setEditError("");
+    try {
+      const updated = await updateImapAccount(editAccount.id, {
+        name: editName,
+        host: editHost,
+        port: parseInt(editPort, 10),
+        tls: editTls,
+        username: editUsername,
+        password: editPassword || undefined,
+      });
+      setAccounts((prev) => prev.map((a) => (a.id === updated.id ? updated : a)));
+      setEditAccount(null);
+    } catch (err) {
+      setEditError(err instanceof Error ? err.message : String(err));
+    } finally {
+      setEditSaving(false);
+    }
+  }
+
   async function handleSyncNow(id: number) {
     try {
       const updated = await triggerImapSync(id);
@@ -407,10 +456,17 @@ export default function ImapPage() {
                     >
                       Sync jetzt
                     </Button>
+                    <Button
+                      size="sm"
+                      variant="outline"
+                      onClick={() => openEdit(acc)}
+                    >
+                      Bearbeiten
+                    </Button>
                     <Button
                       size="sm"
                       variant="destructive"
-                      disabled={acc.status === "running" || acc.sync_running}
+                      disabled={acc.status === "running"}
                       onClick={() => setDeleteConfirm(acc.id)}
                     >
                       Loeschen
@@ -572,6 +628,57 @@ export default function ImapPage() {
           </DialogContent>
         </Dialog>
 
+        {/* Edit Account Dialog */}
+        <Dialog open={editAccount !== null} onOpenChange={(open) => { if (!open) setEditAccount(null); }}>
+          <DialogContent className="max-w-lg">
+            <DialogHeader>
+              <DialogTitle>IMAP-Konto bearbeiten</DialogTitle>
+            </DialogHeader>
+            <div className="space-y-4">
+              <div className="space-y-1">
+                <Label>Name</Label>
+                <Input value={editName} onChange={(e) => setEditName(e.target.value)} placeholder="z.B. Firmen-Mail" />
+              </div>
+              <div className="grid grid-cols-2 gap-3">
+                <div className="space-y-1">
+                  <Label>Host</Label>
+                  <Input value={editHost} onChange={(e) => setEditHost(e.target.value)} placeholder="imap.example.com" />
+                </div>
+                <div className="space-y-1">
+                  <Label>Port</Label>
+                  <Input value={editPort} onChange={(e) => setEditPort(e.target.value)} type="number" />
+                </div>
+              </div>
+              <div className="space-y-1">
+                <Label>TLS</Label>
+                <Select value={editTls} onValueChange={setEditTls}>
+                  <SelectTrigger><SelectValue /></SelectTrigger>
+                  <SelectContent>
+                    <SelectItem value="ssl">SSL/TLS</SelectItem>
+                    <SelectItem value="starttls">STARTTLS</SelectItem>
+                    <SelectItem value="none">Keine</SelectItem>
+                  </SelectContent>
+                </Select>
+              </div>
+              <div className="space-y-1">
+                <Label>Benutzername</Label>
+                <Input value={editUsername} onChange={(e) => setEditUsername(e.target.value)} placeholder="user@example.com" />
+              </div>
+              <div className="space-y-1">
+                <Label>Passwort <span className="text-muted-foreground text-xs">(leer lassen = unveraendert)</span></Label>
+                <Input value={editPassword} onChange={(e) => setEditPassword(e.target.value)} type="password" placeholder="Neues Passwort eingeben" />
+              </div>
+              {editError && <p className="text-sm text-destructive">{editError}</p>}
+            </div>
+            <DialogFooter>
+              <Button variant="outline" onClick={() => setEditAccount(null)}>Abbrechen</Button>
+              <Button onClick={handleEditSave} disabled={editSaving}>
+                {editSaving ? "Speichert..." : "Speichern"}
+              </Button>
+            </DialogFooter>
+          </DialogContent>
+        </Dialog>
+
         {/* Delete Confirmation Dialog */}
         <Dialog
           open={deleteConfirm !== null}

src/lib/api.ts

@@ -392,6 +392,16 @@ export async function updateImapInterval(id: number, intervalMin: number): Promi
   });
 }
 
+export async function updateImapAccount(
+  id: number,
+  data: { name: string; host: string; port: number; tls: string; username: string; password?: string }
+): Promise<ImapAccount> {
+  return request<ImapAccount>(`/api/imap/${id}`, {
+    method: "PATCH",
+    body: JSON.stringify(data),
+  });
+}
+
 // ── POP3 ──────────────────────────────────────────────────────────────────
 
 export interface Pop3Account {