feat: монорепо миграция, Discover/SearxNG улучшения

- Миграция на монорепозиторий (apps/frontend, apps/chat-service, etc.)
- Discover: проверка SearxNG, понятное empty state при ненастроенном поиске
- searxng.ts: валидация URL, проверка JSON-ответа, авто-добавление http://
- docker/searxng-config: настройки для JSON API SearxNG

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/frontend/src/app/api/uploads/route.ts

@@ -0,0 +1,40 @@
+import { NextResponse } from 'next/server';
+import ModelRegistry from '@/lib/models/registry';
+import UploadManager from '@/lib/uploads/manager';
+
+export async function POST(req: Request) {
+  try {
+    const formData = await req.formData();
+
+    const files = formData.getAll('files') as File[];
+    const embeddingModel = formData.get('embedding_model_key') as string;
+    const embeddingModelProvider = formData.get('embedding_model_provider_id') as string;
+
+    if (!embeddingModel || !embeddingModelProvider) {
+      return NextResponse.json(
+        { message: 'Missing embedding model or provider' },
+        { status: 400 },
+      );
+    }
+
+    const registry = new ModelRegistry();
+
+    const model = await registry.loadEmbeddingModel(embeddingModelProvider, embeddingModel);
+    
+    const uploadManager = new UploadManager({
+      embeddingModel: model,
+    })
+
+    const processedFiles = await uploadManager.processFiles(files);
+
+    return NextResponse.json({
+      files: processedFiles,
+    });
+  } catch (error) {
+    console.error('Error uploading file:', error);
+    return NextResponse.json(
+      { message: 'An error has occurred.' },
+      { status: 500 },
+    );
+  }
+}