Server-side scenario execution: effects client replaces local engine

- client.Effects: typed effects + completion methods posting scenario callbacks
- client.Scenario reduced to TriggerAsync
- pending polling via Update() pump: 30s heartbeat + wait-deadline checks
- local engine, plan persistence (IPlanStateStore) and resume removed
- RealtimeService and realtime transports removed (relay never deployed)
- dead IPlanScheduler leftover removed
- models regenerated from openapi (ExecutionPlan/BoundaryNode gone, PendingEffect added)

Models/BoundaryNode.cs

@@ -1,30 +0,0 @@
-// Code generated by apigen. DO NOT EDIT.
-using Newtonsoft.Json;
-using System;
-
-namespace RudderSdk.Core.Models;
-
-public class BoundaryNode
-{
-    [JsonProperty("callbackUrl")]
-    public string? CallbackUrl { get; set; }
-
-    [JsonProperty("enforcement")]
-    public string? Enforcement { get; set; }
-
-    [JsonProperty("enteredAt")]
-    public DateTimeOffset? EnteredAt { get; set; }
-
-    [JsonProperty("nodeId")]
-    public string? NodeId { get; set; }
-
-    [JsonProperty("sourceHandle")]
-    public string? SourceHandle { get; set; }
-
-    [JsonProperty("sourceNodeId")]
-    public string? SourceNodeId { get; set; }
-
-    [JsonProperty("waitDeadline")]
-    public DateTimeOffset? WaitDeadline { get; set; }
-
-}

Models/ExecutionPlan.cs

@@ -1,37 +0,0 @@
-// Code generated by apigen. DO NOT EDIT.
-using Newtonsoft.Json;
-using Newtonsoft.Json.Linq;
-using System.Collections.Generic;
-
-namespace RudderSdk.Core.Models;
-
-public class ExecutionPlan
-{
-    [JsonProperty("boundaryNodes")]
-    public List<BoundaryNode>? BoundaryNodes { get; set; }
-
-    [JsonProperty("context")]
-    public JToken? Context { get; set; }
-
-    [JsonProperty("edges")]
-    public List<PlanEdge>? Edges { get; set; }
-
-    [JsonProperty("nodes")]
-    public List<ExecutionPlanNode>? Nodes { get; set; }
-
-    [JsonProperty("planId")]
-    public string? PlanId { get; set; }
-
-    [JsonProperty("runId")]
-    public string? RunId { get; set; }
-
-    [JsonProperty("scenarioId")]
-    public string? ScenarioId { get; set; }
-
-    [JsonProperty("startNodeId")]
-    public string? StartNodeId { get; set; }
-
-    [JsonProperty("userId")]
-    public string? UserId { get; set; }
-
-}

Models/ExecutionPlanNode.cs

@@ -1,18 +0,0 @@
-// Code generated by apigen. DO NOT EDIT.
-using Newtonsoft.Json;
-using Newtonsoft.Json.Linq;
-
-namespace RudderSdk.Core.Models;
-
-public class ExecutionPlanNode
-{
-    [JsonProperty("data")]
-    public JToken? Data { get; set; }
-
-    [JsonProperty("id")]
-    public string? Id { get; set; }
-
-    [JsonProperty("type")]
-    public string? Type { get; set; }
-
-}

Models/PlanEdge.cs

@@ -1,23 +0,0 @@
-// Code generated by apigen. DO NOT EDIT.
-using Newtonsoft.Json;
-
-namespace RudderSdk.Core.Models;
-
-public class PlanEdge
-{
-    [JsonProperty("id")]
-    public string? Id { get; set; }
-
-    [JsonProperty("source")]
-    public string? Source { get; set; }
-
-    [JsonProperty("sourceHandle")]
-    public string? SourceHandle { get; set; }
-
-    [JsonProperty("target")]
-    public string? Target { get; set; }
-
-    [JsonProperty("targetHandle")]
-    public string? TargetHandle { get; set; }
-
-}