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>

.gitignore

@@ -0,0 +1,16 @@
+.playwright-cli/*
+.playwright-mcp/*
+frontend/node_modules/*
+frontend/dist/*
+frontend/output/*
+frontend/.next/*
+frontend/.vercel/*
+frontend/.vercel_build_output/*
+output/*
+.DS_Store
+.tools/bin/*
+
+# Embedded external tool/skill repos (checked out locally, not vendored)
+.ai-context/ai-context/
+.ai-context/zero-skills/
+.tools/mcp-zero/