refactor(web): drop legacy ModelsDialog, use unified SettingsDialog everywhere

The model-selector in dynamic forms (pipeline / knowledge base settings)
still opened the old standalone ModelsDialog. Point it at the unified
SettingsDialog (section pinned to models) and delete the now-unused
ModelsDialog wrapper so only the new dialog remains.

web/src/app/home/components/models-dialog/ModelsDialog.tsx

@@ -1,42 +0,0 @@
-import { useState } from 'react';
-import {
-  Dialog,
-  DialogContent,
-  DialogHeader,
-  DialogTitle,
-} from '@/components/ui/dialog';
-import { useTranslation } from 'react-i18next';
-import ModelsPanel from './ModelsPanel';
-
-interface ModelsDialogProps {
-  open: boolean;
-  onOpenChange: (open: boolean) => void;
-}
-
-// Standalone Models dialog. The unified Settings dialog renders <ModelsPanel />
-// directly; this wrapper is kept for places that open Models on its own
-// (e.g. the model picker inside dynamic forms).
-export default function ModelsDialog({
-  open,
-  onOpenChange,
-}: ModelsDialogProps) {
-  const { t } = useTranslation();
-  const [blocking, setBlocking] = useState(false);
-
-  return (
-    <Dialog
-      open={open}
-      onOpenChange={(newOpen) => {
-        if (!newOpen && blocking) return;
-        onOpenChange(newOpen);
-      }}
-    >
-      <DialogContent className="overflow-hidden p-0 h-[80vh] flex flex-col !max-w-[37rem]">
-        <DialogHeader className="px-6 pt-6 pb-0 flex-shrink-0">
-          <DialogTitle>{t('models.title')}</DialogTitle>
-        </DialogHeader>
-        <ModelsPanel active={open} onBlockingChange={setBlocking} />
-      </DialogContent>
-    </Dialog>
-  );
-}