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>

frontend/src/ui/components/CanvasZoomMenu/index.css

@@ -0,0 +1,62 @@
+.canvas-zoom-trigger {
+  min-width: 46px;
+  height: 24px;
+  padding: 0 8px;
+  border-radius: 6px;
+  color: #687080;
+  font-size: 13px;
+  font-weight: 720;
+  line-height: 24px;
+  text-align: center;
+}
+
+.canvas-zoom-trigger:hover,
+.canvas-zoom-trigger[data-state="open"] {
+  background: #f2f4f7;
+}
+
+.canvas-zoom-popover {
+  width: 264px;
+  padding: 16px;
+  border: 1px solid rgba(226, 228, 234, 0.9);
+  border-radius: 17px;
+  background: rgba(255, 255, 255, 0.98);
+  box-shadow: 0 14px 34px rgba(17, 24, 39, 0.13);
+}
+
+.canvas-zoom-menu {
+  display: grid;
+  gap: 4px;
+}
+
+.canvas-zoom-menu button {
+  width: 100%;
+  height: 38px;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 0 3px;
+  border-radius: 8px;
+  color: #20242c;
+  background: transparent;
+  font-size: 17px;
+  font-weight: 520;
+  line-height: 1;
+}
+
+.canvas-zoom-menu button:hover {
+  background: #f5f6f8;
+}
+
+.canvas-zoom-menu kbd {
+  color: #afb3ba;
+  font: inherit;
+  font-size: 17px;
+  font-weight: 620;
+}
+
+.canvas-zoom-menu i {
+  height: 1px;
+  margin: 7px 0 8px;
+  background: #eceef2;
+}

frontend/src/ui/components/CanvasZoomMenu/index.tsx

@@ -0,0 +1,69 @@
+"use client";
+
+import { useMemo } from "react";
+import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover";
+import { useI18n } from "@/i18n/i18n";
+import "./index.css";
+
+type ZoomAction = {
+  label: string;
+  shortcut?: string;
+  onSelect: () => void;
+};
+
+export function CanvasZoomMenu({
+  zoom,
+  onZoomIn,
+  onZoomOut,
+  onFitAll,
+  onZoomTo
+}: {
+  zoom: number;
+  onZoomIn: () => void;
+  onZoomOut: () => void;
+  onFitAll: () => void;
+  onZoomTo: (zoom: number) => void;
+}) {
+  const { t } = useI18n();
+  const isMac = useMemo(isApplePlatform, []);
+  const primary = isMac ? "⌘" : "Ctrl";
+  const actions: ZoomAction[] = [
+    { label: t("zoomIn"), shortcut: `${primary} +`, onSelect: onZoomIn },
+    { label: t("zoomOut"), shortcut: `${primary} -`, onSelect: onZoomOut },
+    { label: t("zoomShowAll"), shortcut: isMac ? "⇧ 1" : "Shift 1", onSelect: onFitAll }
+  ];
+  const presets = [0.5, 1, 2];
+
+  return (
+    <Popover>
+      <PopoverTrigger asChild>
+        <button type="button" className="canvas-zoom-trigger" aria-label={t("zoomMenu")} title={t("zoomMenu")}>
+          {Math.round(zoom * 100)}%
+        </button>
+      </PopoverTrigger>
+      <PopoverContent className="canvas-zoom-popover" side="top" align="start" sideOffset={12} onPointerDown={(event) => event.stopPropagation()} onWheel={(event) => event.stopPropagation()}>
+        <div className="canvas-zoom-menu">
+          {actions.map((action) => (
+            <button key={action.label} type="button" onClick={action.onSelect}>
+              <span>{action.label}</span>
+              {action.shortcut && <kbd>{action.shortcut}</kbd>}
+            </button>
+          ))}
+          <i />
+          {presets.map((preset) => (
+            <button key={preset} type="button" onClick={() => onZoomTo(preset)}>
+              <span>{t("zoomTo", { percent: Math.round(preset * 100) })}</span>
+            </button>
+          ))}
+        </div>
+      </PopoverContent>
+    </Popover>
+  );
+}
+
+function isApplePlatform() {
+  if (typeof navigator === "undefined") return false;
+  const nav = navigator as Navigator & { userAgentData?: { platform?: string } };
+  const platform = nav.userAgentData?.platform || navigator.platform || "";
+  return /mac|iphone|ipad|ipod/i.test(platform);
+}