p2p: add network simulation framework (#14982)

This commit introduces a network simulation framework which
can be used to run simulated networks of devp2p nodes. The
intention is to use this for testing protocols, performing
benchmarks and visualising emergent network behaviour.

node/config.go

@@ -128,6 +128,13 @@ type Config struct {
 	// If the module list is empty, all RPC API endpoints designated public will be
 	// exposed.
 	WSModules []string `toml:",omitempty"`
+
+	// WSExposeAll exposes all API modules via the WebSocket RPC interface rather
+	// than just the public ones.
+	//
+	// *WARNING* Only set this if the node is running in a trusted network, exposing
+	// private APIs to untrusted users is a major security risk.
+	WSExposeAll bool `toml:",omitempty"`
 }
 
 // IPCEndpoint resolves an IPC endpoint based on a configured value, taking into