feat: add configurable system messages (#1343)

Co-authored-by: GoClaw Operator <operator@goclaw>

cmd/gateway.go

@@ -48,6 +48,7 @@ import (
 	"github.com/nextlevelbuilder/goclaw/internal/security"
 	"github.com/nextlevelbuilder/goclaw/internal/skills"
 	"github.com/nextlevelbuilder/goclaw/internal/store"
+	"github.com/nextlevelbuilder/goclaw/internal/systemmessages"
 	"github.com/nextlevelbuilder/goclaw/internal/tools"
 	usagecaps "github.com/nextlevelbuilder/goclaw/internal/usage/caps"
 	usagepricing "github.com/nextlevelbuilder/goclaw/internal/usage/pricing"
@@ -689,6 +690,7 @@ func runGateway() {
 
 	// Channel manager
 	channelMgr := channels.NewManager(msgBus)
+	channelMgr.SetSystemMessages(systemmessages.NewResolver(cfg))
 	deps.channelMgr = channelMgr
 
 	// Wire channel member resolver into permission grant paths (WS + HTTP) so

cmd/gateway_channels_setup.go

@@ -24,6 +24,7 @@ import (
 	"github.com/nextlevelbuilder/goclaw/internal/gateway"
 	"github.com/nextlevelbuilder/goclaw/internal/gateway/methods"
 	"github.com/nextlevelbuilder/goclaw/internal/store"
+	"github.com/nextlevelbuilder/goclaw/internal/systemmessages"
 	"github.com/nextlevelbuilder/goclaw/pkg/protocol"
 )
 
@@ -216,13 +217,16 @@ func wireChannelEventSubscribers(
 
 	// Wire pairing approval notification → channel (matching TS notifyPairingApproved).
 	botName := cfg.ResolveDisplayName("default")
+	messageResolver := systemmessages.NewResolver(cfg)
 	pairingMethods.SetOnApprove(func(ctx context.Context, channel, chatID, senderID string) {
 		// Browser/internal channels use WebSocket — UI polls approval status directly.
 		if channels.IsInternalChannel(channel) {
 			slog.Debug("pairing approved for internal channel, skipping notification", "channel", channel)
 			return
 		}
-		msg := fmt.Sprintf("✅ %s access approved. Send a message to start chatting.", botName)
+		msg := messageResolver.Render("", systemmessages.KeyPairingApproved, systemmessages.Vars{
+			"app_name": botName,
+		})
 		// Group pairings need group_id metadata so channels (e.g. Zalo) route to group API.
 		if strings.HasPrefix(senderID, "group:") {
 			msgBus.PublishOutbound(bus.OutboundMessage{