fix: add involves edge from task to agent:nomos at creation

Plus sync vendor directory for Docker build compatibility.

vendor/github.com/modelcontextprotocol/go-sdk/internal/xcontext/xcontext.go

@@ -0,0 +1,23 @@
+// Copyright 2019 The Go MCP SDK Authors. All rights reserved.
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// Package xcontext is a package to offer the extra functionality we need
+// from contexts that is not available from the standard context package.
+package xcontext
+
+import (
+	"context"
+	"time"
+)
+
+// Detach returns a context that keeps all the values of its parent context
+// but detaches from the cancellation and error handling.
+func Detach(ctx context.Context) context.Context { return detachedContext{ctx} }
+
+type detachedContext struct{ parent context.Context }
+
+func (v detachedContext) Deadline() (time.Time, bool) { return time.Time{}, false }
+func (v detachedContext) Done() <-chan struct{}       { return nil }
+func (v detachedContext) Err() error                  { return nil }
+func (v detachedContext) Value(key any) any           { return v.parent.Value(key) }