feat(previs): 图片生成预演台 - 从图片节点交给 Agent 复现为可编辑 3D 预演

图片工具栏新增「生成预演台」，自动选用支持看图的文本模型并提交复现指令。对话用节点卡片展示「此图」，普通图片演员只写名称时不再要求角色卡绑定。

web/test/agent-chat-node-links.test.tsx

@@ -64,6 +64,23 @@ test("renders an agent node link as a titled inline node card", () => {
     expect(visibleText).not.toContain("video-1790385749473-q4157");
 });
 
+test("renders the image-to-previs user request with the existing canvas node card", () => {
+    const imageReference = { ...videoReference, kind: "image" as const, sourceType: "image" as const, label: "道姑", title: "道姑" };
+    const html = renderToStaticMarkup(
+        <AgentChatMessage
+            item={{ id: "user-previs", role: "user", text: "根据此图生成 3D 预演台", canvasReferenceNodeId: imageReference.nodeId }}
+            theme={canvasThemes.dark}
+            references={[imageReference]}
+            onFocusNode={() => {}}
+        />,
+    );
+
+    expect(html).toContain('class="agent-message-node-link"');
+    expect(html).toContain('class="agent-message-node-link-preview"');
+    expect(html).toContain("道姑");
+    expect(html).toContain("3D 预演台");
+});
+
 test("labels character cards by resource kind instead of the underlying text type", () => {
     const nodeId = "text-1790385749473-char1";
     const reference = { id: nodeId, nodeId, kind: "character" as const, label: "李莫愁", title: "李莫愁", sourceType: "text" as const };

web/test/canvas-node-toolbar.test.ts

@@ -91,5 +91,7 @@ describe("canvas node toolbar model", () => {
         expect(tools.find((tool) => tool.id === "crop")?.section).toBe("构图与尺寸");
         expect(tools.find((tool) => tool.id === "resize")?.active).toBe(true);
         expect(tools.find((tool) => tool.id === "copyPrompt")?.group).toBe("more");
+        expect(tools.find((tool) => tool.id === "previs")?.group).toBe("primary");
+        expect(tools.find((tool) => tool.id === "previs")?.description).toContain("Agent");
     });
 });

web/test/image-to-previs-agent.test.ts

@@ -0,0 +1,111 @@
+import { describe, expect, test } from "bun:test";
+
+import { buildImageToPrevisAgentPrompt, buildImageToPrevisDisplayText, modelSupportsImageInspection, selectImageInspectionModel } from "@/lib/canvas/image-to-previs-agent";
+import type { AiConfig } from "@/stores/use-config-store";
+
+describe("image to previs Agent prompt", () => {
+    test("requires visual inspection and editable semantic objects", () => {
+        const prompt = buildImageToPrevisAgentPrompt({
+            id: "image-ref",
+            nodeId: "image-node-1",
+            kind: "image",
+            label: "场景图",
+            title: "场景图",
+            active: true,
+            mentionToken: "@[node:image-node-1]",
+        });
+
+        expect(prompt).toContain("@[node:image-node-1]");
+        expect(prompt).toContain("canvas_inspect_image");
+        expect(prompt).toContain("不要改用 image_text_detect");
+        expect(prompt).toContain("previs_scene_create");
+        expect(prompt).toContain("previs_scene_read");
+        expect(prompt).toContain("previs_apply_patch");
+        expect(prompt).toContain("actor");
+        expect(prompt).toContain("不要把原图作为 billboard");
+        expect(prompt).toContain("普通图片中的人物不是角色卡");
+        expect(prompt).toContain("禁止传 characterName");
+        expect(prompt).not.toContain("createPrevisBillboard");
+        expect(buildImageToPrevisDisplayText()).toBe("根据此图生成 3D 预演台");
+    });
+
+    test("routes the image workflow to a configured vision-capable text model", () => {
+        const config = {
+            channels: [
+                {
+                    id: "plain",
+                    scope: "system",
+                    models: ["plain-text"],
+                    modelCosts: [
+                        {
+                            model: "plain-text",
+                            capability: "text",
+                            protocol: "chat-completion",
+                            billingMode: "fixed_request",
+                            unitPriceMicrocredits: 1,
+                            capabilityConfig: { version: 1, text: { contextWindowTokens: 128000, maxOutputTokens: 16384, references: { promptMaxChars: 32000, maxImages: 0, maxImageBytes: 0, maxVideos: 0, maxVideoBytes: 0 } } },
+                        },
+                    ],
+                },
+                {
+                    id: "vision",
+                    scope: "system",
+                    models: ["vision-text"],
+                    modelCosts: [
+                        {
+                            model: "vision-text",
+                            capability: "text",
+                            protocol: "chat-completion",
+                            billingMode: "fixed_request",
+                            unitPriceMicrocredits: 1,
+                            capabilityConfig: { version: 1, text: { contextWindowTokens: 128000, maxOutputTokens: 16384, references: { promptMaxChars: 32000, maxImages: 3, maxImageBytes: 30 * 1024 * 1024, maxVideos: 0, maxVideoBytes: 0 } } },
+                        },
+                    ],
+                },
+            ],
+        } as AiConfig;
+
+        expect(modelSupportsImageInspection(config, "plain::plain-text")).toBe(false);
+        expect(selectImageInspectionModel(config, "plain::plain-text")).toBe("vision::vision-text");
+        expect(selectImageInspectionModel(config, "vision::vision-text")).toBe("vision::vision-text");
+    });
+
+    test("does not route the cloud Agent through a browser-only custom channel", () => {
+        const config = {
+            channels: [
+                {
+                    id: "custom",
+                    scope: "user",
+                    models: ["custom-vision"],
+                    modelCosts: [
+                        {
+                            model: "custom-vision",
+                            capability: "text",
+                            protocol: "chat-completion",
+                            billingMode: "fixed_request",
+                            unitPriceMicrocredits: 1,
+                            capabilityConfig: { version: 1, text: { contextWindowTokens: 128000, maxOutputTokens: 16384, references: { promptMaxChars: 32000, maxImages: 3, maxImageBytes: 30 * 1024 * 1024, maxVideos: 0, maxVideoBytes: 0 } } },
+                        },
+                    ],
+                },
+                {
+                    id: "managed",
+                    scope: "system",
+                    models: ["managed-vision"],
+                    modelCosts: [
+                        {
+                            model: "managed-vision",
+                            capability: "text",
+                            protocol: "chat-completion",
+                            billingMode: "fixed_request",
+                            unitPriceMicrocredits: 1,
+                            capabilityConfig: { version: 1, text: { contextWindowTokens: 128000, maxOutputTokens: 16384, references: { promptMaxChars: 32000, maxImages: 3, maxImageBytes: 30 * 1024 * 1024, maxVideos: 0, maxVideoBytes: 0 } } },
+                        },
+                    ],
+                },
+            ],
+        } as unknown as AiConfig;
+
+        expect(selectImageInspectionModel(config, "custom::custom-vision")).toBe("managed::managed-vision");
+    });
+});