docs: polish README and trim migration commentary

Author: teovl

README.md

@@ -1,42 +1,40 @@
 # runtime
 
-Pilot Protocol runtime glue. Wires the major subsystems together for
-the daemon process: handshake, policy, identity, events, streams. This
-is the package the daemon's `main.go` constructs and hands to the plugin
-register.
+Runtime glue for the Pilot Protocol daemon. Wires the major subsystems
+together — handshake, policy, identity, events, streams — into a single
+`Runtime` value the daemon's `main.go` constructs and hands to the
+plugin register.
 
-## Layout
-
-| File | What it does |
-|---|---|
-| `runtime.go` | `Runtime` struct + plugin registration / lifecycle. |
-| `identity.go` | Load/save Ed25519 identity from disk. |
-| `events.go` | In-process event bus implementation. |
-| `streams.go` | `coreapi.Streams` listener registry on top of the driver. |
-| `handshake.go` | Adapter that exposes the handshake plugin to the runtime. |
-| `policy.go` | Adapter that exposes the policy plugin to the runtime. |
-| `policy_manager.go` | Per-network policy-file load + reload helpers. |
-
-## Import paths
+## Install
 
 ```go
 import "github.com/pilot-protocol/runtime"
+```
 
+## Usage
+
+```go
 rt, err := runtime.New(runtime.Config{
     IdentityPath: "~/.pilot/identity.json",
     PolicyDir:    "~/.pilot/policy",
     // ...
 })
+if err != nil {
+    return err
+}
 rt.Register(handshakeService)
 rt.Register(policyService)
 rt.Run(ctx)
 ```
 
-This package is intentionally the last to extract — it depends on
-both `pilot-protocol/handshake` and `pilot-protocol/policy`.
-
-## Releasing
+## Layout
 
-Tag a SemVer version (e.g. `v0.1.0`); web4 pulls it in via
-`require github.com/pilot-protocol/runtime v0.1.0`. During
-co-development the protocol repo uses `replace ../runtime`.
+| File | What it does |
+|---|---|
+| `runtime.go` | `Runtime` struct, plugin registration, lifecycle. |
+| `identity.go` | Load/save Ed25519 identity from disk. |
+| `events.go` | In-process event bus implementation. |
+| `streams.go` | `coreapi.Streams` listener registry on top of the driver. |
+| `handshake.go` | Adapter that exposes the handshake plugin to the runtime. |
+| `policy.go` | Adapter that exposes the policy plugin to the runtime. |
+| `policy_manager.go` | Per-network policy-file load and reload helpers. |