Enhance logging and add policy test client

- Refactored logOutput function to trace-log stdout and stderr lines for better debugging.
- Introduced a new policy test client in cmd/policytest/main.go to publish events and check policy responses.
- Added a script to run the policy test, ensuring proper cleanup and error handling.
- Updated policy event processing to ensure newline-terminated JSON for compatibility with shell-readers.

cmd/policytest/main.go

@@ -0,0 +1,60 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"time"
+
+	"lol.mleku.dev/chk"
+	"lol.mleku.dev/log"
+	"next.orly.dev/pkg/crypto/p256k"
+	"next.orly.dev/pkg/encoders/event"
+	"next.orly.dev/pkg/encoders/kind"
+	"next.orly.dev/pkg/encoders/tag"
+	"next.orly.dev/pkg/protocol/ws"
+)
+
+func main() {
+	var err error
+	url := flag.String("url", "ws://127.0.0.1:3334", "relay websocket URL")
+	timeout := flag.Duration("timeout", 20*time.Second, "publish timeout")
+	flag.Parse()
+
+	// Minimal client that publishes a single kind 4678 event and reports OK/err
+	var rl *ws.Client
+	if rl, err = ws.RelayConnect(context.Background(), *url); chk.E(err) {
+		log.E.F("connect error: %v", err)
+		return
+	}
+	defer rl.Close()
+
+	signer := &p256k.Signer{}
+	if err = signer.Generate(); chk.E(err) {
+		log.E.F("signer generate error: %v", err)
+		return
+	}
+
+	ev := &event.E{
+		CreatedAt: time.Now().Unix(),
+		Kind:      kind.K{K: 4678}.K, // arbitrary custom kind
+		Tags:      tag.NewS(),
+		Content:   []byte("policy test: expect rejection"),
+	}
+	if err = ev.Sign(signer); chk.E(err) {
+		log.E.F("sign error: %v", err)
+		return
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), *timeout)
+	defer cancel()
+
+	if err = rl.Publish(ctx, ev); err != nil {
+		// Expected path if policy rejects: client returns error with reason (from OK false)
+		fmt.Println("policy reject:", err)
+		return
+	}
+
+	log.I.Ln("publish result: accepted")
+	fmt.Println("ACCEPT")
+}