Initial commit: img-infinite-canvas AI design workbench MVP

Moteva-style AI design workbench replica. Home prompt creates a project;
the project page provides an infinite canvas with node drag, zoom/pan,
a design chat panel, history replay, image asset upload, and project
save/regenerate.

- Backend: go-zero, DDD layering, sqlc/pgx, optional PostgreSQL; memory
  or Redis cache; asynq job queue; MinIO/S3/R2/OSS object storage;
  sky-valley/pi agent runtime adapter.
- Frontend: Next.js App Router + Vite artifact build, TypeScript, i18n,
  shadcn/ui components, auth (OTP/Turnstile/Google/WeChat).
- Deploy: Docker Compose and k3s manifests.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

server/internal/infrastructure/piagent/creative_agent_test.go

@@ -0,0 +1,39 @@
+package piagent
+
+import (
+	"strings"
+	"testing"
+	"unicode/utf8"
+
+	"img_infinite_canvas/internal/domain/design"
+)
+
+func TestNewCreativeAgentDefaultsToGPT55(t *testing.T) {
+	agent := NewCreativeAgent(CreativeAgentOptions{
+		BaseURL: "http://example.com",
+		APIKey:  "test-key",
+	})
+	if agent == nil {
+		t.Fatal("expected creative agent")
+	}
+	if agent.model != "gpt-5.5" {
+		t.Fatalf("expected gpt-5.5 default model, got %s", agent.model)
+	}
+}
+
+func TestAgentMessageContentSummaryDoesNotLeakImageURLs(t *testing.T) {
+	summary := agentMessageContentSummary([]design.AgentChatMessage{
+		{
+			Contents: []design.AgentContent{
+				{Type: "text", Text: strings.Repeat("视觉方向", 200)},
+				{Type: "image", ImageURL: "https://storage.example.com/private/raw.png", ImageWidth: 100, ImageHeight: 200},
+			},
+		},
+	})
+	if strings.Contains(summary, "storage.example.com") || strings.Contains(summary, "raw.png") {
+		t.Fatalf("expected compact image reference without raw URL, got %s", summary)
+	}
+	if utf8.RuneCountInString(summary) > 360 {
+		t.Fatalf("expected compact inline text summary, got %d runes", utf8.RuneCountInString(summary))
+	}
+}