feat(canvas): 画布媒体工作流 - 支持批量连线、失败重试与模型能力增强

合并 PR #230。保留当前主线样式与组件结构，吸收批量连线、失败批次重试、媒体模型能力和相关后端增强，并修复集成检查发现的分辨率选择器启用条件与测试稳定性问题。

web/test/canvas-batch-connection.test.ts

@@ -0,0 +1,115 @@
+import { describe, expect, it } from "bun:test";
+
+import { buildBatchConnectionCreateRequest, hasBatchConnectionCandidate, planBatchConnections } from "@/lib/canvas/canvas-batch-connection";
+import { defaultConfig } from "@/stores/use-config-store";
+import { CanvasNodeType, type CanvasConnection, type CanvasNodeData } from "@/types/canvas";
+
+const nodes: CanvasNodeData[] = [
+    { id: "text-a", type: CanvasNodeType.Text, title: "文本 A", position: { x: 0, y: 0 }, width: 320, height: 180 },
+    { id: "text-b", type: CanvasNodeType.Text, title: "文本 B", position: { x: 0, y: 220 }, width: 320, height: 180 },
+    { id: "image-a", type: CanvasNodeType.Image, title: "图片 A", position: { x: 0, y: 440 }, width: 320, height: 180 },
+    { id: "image-b", type: CanvasNodeType.Image, title: "图片 B", position: { x: 0, y: 660 }, width: 320, height: 180 },
+    { id: "script", type: CanvasNodeType.Script, title: "分镜脚本", position: { x: 520, y: 0 }, width: 640, height: 520, metadata: { storyboard: { rows: [{ id: "row-1", shotNumber: 1, durationSeconds: 6, plotDescription: "", dialogue: "", characters: [], narrativeIntent: "", viewerPOV: "", performanceBlocking: "", shotSize: "", emotion: "", lightingAndAtmosphere: "", audioEffects: "", camera: "", motion: "", timeBeats: "", imageGenerationPrompt: "", videoMotionPrompt: "", mustHave: [], optionalDetails: [], continuityOut: "", negativePrompt: "", referenceNodeIds: [], status: "idle" }] } } },
+    { id: "config", type: CanvasNodeType.Config, title: "图片配置", position: { x: 520, y: 560 }, width: 360, height: 420, metadata: { generationMode: "image" } },
+    { id: "frame", type: CanvasNodeType.Frame, title: "背板", position: { x: 0, y: 680 }, width: 500, height: 500 },
+];
+
+const baseConfig = { ...defaultConfig };
+
+describe("planBatchConnections", () => {
+    it("plans all legal source nodes and preserves the target handle", () => {
+        const result = planBatchConnections({
+            sourceNodeIds: ["text-a", "text-b"],
+            targetNodeId: "script",
+            targetHandleId: "row:row-1",
+            targetAnchorRatio: 0.4,
+            nodes,
+            connections: [],
+            config: baseConfig,
+        });
+
+        expect(result.connected).toEqual(["text-a", "text-b"]);
+        expect(result.connections).toHaveLength(2);
+        expect(result.connections.every((connection) => connection.toNodeId === "script" && connection.toHandleId === "row:row-1")).toBe(true);
+        expect(result.skipped).toEqual([]);
+    });
+
+    it("skips duplicate connections without creating another edge", () => {
+        const existing: CanvasConnection[] = [{ id: "existing", fromNodeId: "text-a", toNodeId: "config" }];
+        const result = planBatchConnections({
+            sourceNodeIds: ["text-a", "text-b"],
+            targetNodeId: "config",
+            nodes,
+            connections: existing,
+            config: baseConfig,
+        });
+
+        expect(result.connected).toEqual(["text-b"]);
+        expect(result.duplicates).toEqual(["text-a"]);
+        expect(result.connections).toHaveLength(1);
+    });
+
+    it("reports sources that cannot be used by the aggregate connector", () => {
+        const result = planBatchConnections({
+            sourceNodeIds: ["frame", "text-a"],
+            targetNodeId: "config",
+            nodes,
+            connections: [],
+            config: baseConfig,
+        });
+
+        expect(result.connected).toEqual(["text-a"]);
+        expect(result.skipped).toEqual([{ nodeId: "frame", reason: "背板不能作为连接源" }]);
+    });
+
+    it("keeps every legal graph edge when a newly created node exceeds provider reference capacity", () => {
+        const constrainedConfig = {
+            ...baseConfig,
+            channels: [{
+                id: "grok",
+                name: "Grok",
+                baseUrl: "https://example.com",
+                apiKey: "test-key",
+                apiFormat: "openai" as const,
+                models: ["grok-imagine-image"],
+                modelCosts: [{ model: "grok-imagine-image", capability: "image" as const, billingMode: "fixed_request" as const, unitPriceMicrocredits: 1, protocol: "grok-image" as const }],
+            }],
+            models: ["grok::grok-imagine-image"],
+            imageModels: ["grok::grok-imagine-image"],
+            imageModel: "grok::grok-imagine-image",
+            model: "grok::grok-imagine-image",
+        };
+        const result = planBatchConnections({
+            sourceNodeIds: ["image-a", "image-b"],
+            targetNodeId: "new-image",
+            nodes: [...nodes, { id: "new-image", type: CanvasNodeType.Image, title: "新图片", position: { x: 1200, y: 0 }, width: 320, height: 180 }],
+            connections: [],
+            config: constrainedConfig,
+            allowCapacityOverflow: true,
+        });
+        expect(result.connected).toEqual(["image-a", "image-b"]);
+        expect(result.connections).toHaveLength(2);
+    });
+});
+
+describe("buildBatchConnectionCreateRequest", () => {
+    it("keeps unique eligible sources and uses the first one for the pending connection", () => {
+        const request = buildBatchConnectionCreateRequest(["frame", "text-a", "text-a", "text-b"], nodes, { x: 900, y: 240 });
+
+        expect(request).toEqual({
+            batchSourceNodeIds: ["text-a", "text-b"],
+            connection: { nodeId: "text-a", handleType: "source" },
+            position: { x: 900, y: 240 },
+        });
+    });
+
+    it("returns null when no selected node can be used as a batch source", () => {
+        expect(buildBatchConnectionCreateRequest(["frame", "script", "config"], nodes, { x: 0, y: 0 })).toBeNull();
+    });
+});
+
+describe("hasBatchConnectionCandidate", () => {
+    it("accepts a target when another selected source is legal even if the target itself is selected first", () => {
+        expect(hasBatchConnectionCandidate(["config", "text-a"], "config", nodes)).toBe(true);
+    });
+});