feat: Go backend, enhanced search, new widgets, Docker deploy

Major changes:
- Add Go backend (backend/) with microservices architecture
- Enhanced master-agents-svc: reranker, content-classifier, stealth-crawler,
  proxy-manager, media-search, fastClassifier, language detection
- New web-svc widgets: KnowledgeCard, ProductCard, ProfileCard, VideoCard,
  UnifiedCard, CardGallery, InlineImageGallery, SourcesPanel, RelatedQuestions
- Improved discover-svc with discover-db integration
- Docker deployment improvements (Caddyfile, vendor.sh, BUILD.md)
- Library-svc: project_id schema migration
- Remove deprecated finance-svc and travel-svc
- Localization improvements across services

Made-with: Cursor

backend/webui/src/lib/hooks/useChat.ts

@@ -0,0 +1,177 @@
+'use client';
+
+import { useState, useCallback, useRef } from 'react';
+import type { Message, Citation, Widget, StreamEvent } from '../types';
+import { streamChat, generateId } from '../api';
+
+interface UseChatOptions {
+  onError?: (error: Error) => void;
+}
+
+export function useChat(options: UseChatOptions = {}) {
+  const [messages, setMessages] = useState<Message[]>([]);
+  const [isLoading, setIsLoading] = useState(false);
+  const [citations, setCitations] = useState<Citation[]>([]);
+  const [widgets, setWidgets] = useState<Widget[]>([]);
+  const abortControllerRef = useRef<AbortController | null>(null);
+
+  const sendMessage = useCallback(async (content: string, mode: 'speed' | 'balanced' | 'quality' = 'balanced') => {
+    if (!content.trim() || isLoading) return;
+
+    const userMessage: Message = {
+      id: generateId(),
+      role: 'user',
+      content: content.trim(),
+      createdAt: new Date(),
+    };
+
+    const assistantMessage: Message = {
+      id: generateId(),
+      role: 'assistant',
+      content: '',
+      citations: [],
+      widgets: [],
+      isStreaming: true,
+      createdAt: new Date(),
+    };
+
+    setMessages((prev) => [...prev, userMessage, assistantMessage]);
+    setIsLoading(true);
+    setCitations([]);
+    setWidgets([]);
+
+    const history: [string, string][] = messages
+      .filter((m) => !m.isStreaming)
+      .reduce((acc, m, i, arr) => {
+        if (m.role === 'user' && arr[i + 1]?.role === 'assistant') {
+          acc.push([m.content, arr[i + 1].content]);
+        }
+        return acc;
+      }, [] as [string, string][]);
+
+    try {
+      const stream = streamChat({
+        message: {
+          messageId: assistantMessage.id,
+          chatId: userMessage.id,
+          content: content.trim(),
+        },
+        optimizationMode: mode,
+        history,
+        locale: 'ru',
+      });
+
+      let fullContent = '';
+      const collectedCitations: Citation[] = [];
+      const collectedWidgets: Widget[] = [];
+
+      for await (const event of stream) {
+        switch (event.type) {
+          case 'messageStart':
+            break;
+
+          case 'message':
+            if (event.data && typeof event.data === 'object' && 'content' in event.data) {
+              const chunk = (event.data as { content: string }).content;
+              fullContent += chunk;
+              setMessages((prev) =>
+                prev.map((m) =>
+                  m.id === assistantMessage.id
+                    ? { ...m, content: fullContent }
+                    : m
+                )
+              );
+            }
+            break;
+
+          case 'sources':
+            if (event.data && Array.isArray(event.data)) {
+              const sources = event.data as Array<{
+                url: string;
+                title?: string;
+                metadata?: { title?: string };
+              }>;
+              sources.forEach((source, idx) => {
+                const citation: Citation = {
+                  index: idx + 1,
+                  url: source.url,
+                  title: source.title || source.metadata?.title || new URL(source.url).hostname,
+                  domain: new URL(source.url).hostname,
+                };
+                collectedCitations.push(citation);
+              });
+              setCitations([...collectedCitations]);
+            }
+            break;
+
+          case 'widget':
+            if (event.data && typeof event.data === 'object') {
+              const widget = event.data as Widget;
+              collectedWidgets.push(widget);
+              setWidgets([...collectedWidgets]);
+            }
+            break;
+
+          case 'messageEnd':
+            setMessages((prev) =>
+              prev.map((m) =>
+                m.id === assistantMessage.id
+                  ? {
+                      ...m,
+                      content: fullContent,
+                      citations: collectedCitations,
+                      widgets: collectedWidgets,
+                      isStreaming: false,
+                    }
+                  : m
+              )
+            );
+            break;
+
+          case 'error':
+            throw new Error(
+              event.data && typeof event.data === 'object' && 'message' in event.data
+                ? String((event.data as { message: string }).message)
+                : 'Unknown error'
+            );
+        }
+      }
+    } catch (error) {
+      const errorMessage = error instanceof Error ? error.message : 'Ошибка при отправке сообщения';
+      setMessages((prev) =>
+        prev.map((m) =>
+          m.id === assistantMessage.id
+            ? { ...m, content: `Ошибка: ${errorMessage}`, isStreaming: false }
+            : m
+        )
+      );
+      options.onError?.(error instanceof Error ? error : new Error(errorMessage));
+    } finally {
+      setIsLoading(false);
+    }
+  }, [isLoading, messages, options]);
+
+  const stopGeneration = useCallback(() => {
+    abortControllerRef.current?.abort();
+    setIsLoading(false);
+    setMessages((prev) =>
+      prev.map((m) => (m.isStreaming ? { ...m, isStreaming: false } : m))
+    );
+  }, []);
+
+  const clearMessages = useCallback(() => {
+    setMessages([]);
+    setCitations([]);
+    setWidgets([]);
+  }, []);
+
+  return {
+    messages,
+    isLoading,
+    citations,
+    widgets,
+    sendMessage,
+    stopGeneration,
+    clearMessages,
+  };
+}