feat(agent): Agent 工作台 - 计划插话记忆、统一模型选择器并修复摘要与视频入库

将计划清单、运行中插话和个人记忆接入云端 Agent；全站模型选择器统一为左右二级菜单。画布摘要按预算截断不再整轮拒绝，首页视频未知宽高可入库。README 补充贡献者 morrow。

Co-authored-by: Cursor <cursoragent@cursor.com>

web/src/lib/canvas/agent-approval-presentation.ts

@@ -41,7 +41,7 @@ function fieldLabel(key: string, nodeType: string): string {
 }
 
 function operation(value: unknown): AgentApprovalPreviewOperation | null {
-    return value === "add_node" || value === "update_node" || value === "connect_nodes" || value === "generate_media" || value === "create_storyboard" || value === "edit_storyboard" ? value : null;
+    return value === "add_node" || value === "update_node" || value === "connect_nodes" || value === "generate_media" || value === "create_storyboard" || value === "edit_storyboard" || value === "plan_step" ? value : null;
 }
 
 function normalizeServerPreview(value: unknown): AgentApprovalPresentation | null {