feat: CI/CD pipeline + Learning/Medicine/Travel services

- Add Gitea Actions workflow for automated build & deploy
- Add K8s manifests: webui, travel-svc, medicine-svc, sandbox-svc
- Update kustomization for localhost:5000 registry
- Add ingress for gooseek.ru and api.gooseek.ru
- Learning cabinet with onboarding, courses, sandbox integration
- Medicine service with symptom analysis and doctor matching
- Travel service with itinerary planning
- Server setup scripts (NVIDIA/CUDA, K3s, Gitea runner)

Made-with: Cursor

backend/internal/learning/stepper.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"regexp"
 	"time"
 
 	"github.com/gooseek/backend/internal/llm"
@@ -680,12 +679,7 @@ func (l *StepByStepLesson) SubmitQuizAnswer(stepIndex int, selectedOptions []str
 }
 
 func extractJSON(text string) string {
-	re := regexp.MustCompile(`(?s)\{.*\}`)
-	match := re.FindString(text)
-	if match != "" {
-		return match
-	}
-	return "{}"
+	return extractJSONBlock(text)
 }
 
 func (l *StepByStepLesson) ToJSON() ([]byte, error) {