feat(canvas): 生成合同 - 统一节点参数并补充模型上下文能力

web/src/types/canvas.ts

@@ -6,6 +6,7 @@ import type { StyleExecutionPlan } from "@/lib/canvas/style-profile";
 import type { ArtCritiqueNodeState } from "@/lib/art-critique/contracts";
 import type { CameraControlOptions } from "@/lib/canvas/camera-prompt-library";
 import type { SrtEntry, SubtitleHighlight, SubtitleStyle } from "@/types/timeline";
+import type { GenerationSpec } from "@/lib/canvas/generation-contract.generated";
 
 export type Position = {
     x: number;
@@ -200,6 +201,8 @@ export type CanvasSkillSnapshot = {
 };
 
 export type CanvasNodeMetadata = {
+    /** Credential-free editable generation contract; submitted recipes live with tasks. */
+    generationSpec?: GenerationSpec;
     /** Namespaced extension ownership for nodes contributed by a unified plugin. */
     pluginId?: string;
     pluginNodeId?: string;