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

test-chat-via-webui.sh

@@ -0,0 +1,58 @@
+#!/bin/bash
+
+echo "Testing Chat via WebUI (localhost:3000)"
+echo "========================================"
+echo ""
+
+# Generate unique IDs
+MESSAGE_ID="msg-$(date +%s)-$$"
+CHAT_ID="chat-$(date +%s)-$$"
+
+# Create the request payload with minimal required fields
+PAYLOAD=$(cat <<EOF
+{
+  "message": {
+    "messageId": "$MESSAGE_ID",
+    "chatId": "$CHAT_ID",
+    "content": "Привет, как дела?"
+  },
+  "optimizationMode": "balanced",
+  "history": [],
+  "locale": "ru"
+}
+EOF
+)
+
+echo "Sending chat request to http://localhost:3000/api/chat"
+echo "Message: Привет, как дела?"
+echo ""
+
+# Send request and capture response
+RESPONSE=$(curl -s -X POST http://localhost:3000/api/chat \
+  -H "Content-Type: application/json" \
+  -d "$PAYLOAD" \
+  --max-time 30 \
+  2>&1)
+
+EXIT_CODE=$?
+
+echo "Response:"
+echo "========="
+if [ $EXIT_CODE -eq 0 ]; then
+    if [ -z "$RESPONSE" ]; then
+        echo "⚠ Empty response received"
+    else
+        # Show first 100 lines of response
+        echo "$RESPONSE" | head -100
+        echo ""
+        LINE_COUNT=$(echo "$RESPONSE" | wc -l)
+        echo "Total lines: $LINE_COUNT"
+        echo "Response length: $(echo "$RESPONSE" | wc -c) bytes"
+    fi
+else
+    echo "✗ Request failed with exit code: $EXIT_CODE"
+    echo "$RESPONSE"
+fi
+
+echo ""
+echo "========================================"