fix(monitor): push full message content via ChannelPush, not counts

Monitor checkInbox now sends each new message as a ChannelPush with
from/subject/content — lands directly in the Claude Code session.
Removes the useless InboxMessage{New, Total} count relay through runner.

Co-Authored-By: Virgil <virgil@lethean.io>

pkg/messages/messages.go

@@ -121,10 +121,11 @@ type HarvestRejected struct {
 	Reason string
 }
 
-// InboxMessage is broadcast when new inter-agent messages arrive.
+// InboxMessage is broadcast when a new inter-agent message arrives.
 //
-//	c.ACTION(messages.InboxMessage{New: 2, Total: 15})
+//	c.ACTION(messages.InboxMessage{From: "charon", Subject: "status", Content: "all green"})
 type InboxMessage struct {
-	New   int
-	Total int
+	From    string
+	Subject string
+	Content string
 }

pkg/messages/messages_test.go

@@ -24,7 +24,7 @@ func TestMessages_AllSatisfyMessage_Good(t *testing.T) {
 		RateLimitDetected{Pool: "codex", Duration: "30m"},
 		HarvestComplete{Repo: "go-io", Branch: "agent/fix", Files: 5},
 		HarvestRejected{Repo: "go-io", Branch: "agent/fix", Reason: "binary detected"},
-		InboxMessage{New: 2, Total: 15},
+		InboxMessage{From: "charon", Subject: "test", Content: "hello"},
 	}
 
 	assert.Len(t, msgs, 12, "expected 12 message types")

pkg/monitor/monitor.go

@@ -537,9 +537,18 @@ func (m *Subsystem) checkInbox() string {
 		return ""
 	}
 
-	// Push channel event with full message content
+	// Push each message as a channel event so it lands in the session
 	if m.ServiceRuntime != nil {
-		m.Core().ACTION(messages.InboxMessage{New: len(newMessages), Total: unread})
+		for _, msg := range newMessages {
+			m.Core().ACTION(coremcp.ChannelPush{
+				Channel: "inbox.message",
+				Data: map[string]any{
+					"from":    msg.From,
+					"subject": msg.Subject,
+					"content": msg.Content,
+				},
+			})
+		}
 	}
 
 	return core.Sprintf("%d unread message(s) in inbox", unread)

pkg/monitor/monitor_test.go

@@ -12,6 +12,7 @@ import (
 
 	"dappco.re/go/agent/pkg/messages"
 	core "dappco.re/go/core"
+	coremcp "dappco.re/go/mcp/pkg/mcp"
 	"dappco.re/go/core/process"
 	"github.com/modelcontextprotocol/go-sdk/mcp"
 	"github.com/stretchr/testify/assert"
@@ -259,11 +260,11 @@ func TestMonitor_CheckInbox_Good_UnreadMessages(t *testing.T) {
 	t.Setenv("CORE_API_URL", srv.URL)
 	t.Setenv("AGENT_NAME", "test-agent")
 
-	// Create Core with IPC handler to capture InboxMessage
-	var captured []messages.InboxMessage
+	// Create Core with IPC handler to capture ChannelPush
+	var captured []coremcp.ChannelPush
 	c := core.New()
 	c.RegisterAction(func(_ *core.Core, msg core.Message) core.Result {
-		if ev, ok := msg.(messages.InboxMessage); ok {
+		if ev, ok := msg.(coremcp.ChannelPush); ok {
 			captured = append(captured, ev)
 		}
 		return core.Result{OK: true}
@@ -276,9 +277,11 @@ func TestMonitor_CheckInbox_Good_UnreadMessages(t *testing.T) {
 	msg := mon.checkInbox()
 	assert.Contains(t, msg, "2 unread message(s) in inbox")
 
-	require.Len(t, captured, 1)
-	assert.Equal(t, 3, captured[0].New)
-	assert.Equal(t, 2, captured[0].Total)
+	// 3 new messages (ids 1,2,3 all > prevMaxID=0), but only 2 unread
+	// Monitor sends one ChannelPush per NEW message (higher ID than last seen)
+	require.Len(t, captured, 3)
+	data := captured[0].Data.(map[string]any)
+	assert.Equal(t, "clotho", data["from"])
 }
 
 func TestMonitor_CheckInbox_Good_NoUnread(t *testing.T) {
@@ -373,11 +376,11 @@ func TestMonitor_CheckInbox_Good_MultipleSameSender(t *testing.T) {
 
 	setupAPIEnv(t, srv.URL)
 
-	// Create Core with IPC handler to capture InboxMessage
-	var captured []messages.InboxMessage
+	// Create Core with IPC handler to capture ChannelPush
+	var captured []coremcp.ChannelPush
 	c := core.New()
 	c.RegisterAction(func(_ *core.Core, msg core.Message) core.Result {
-		if ev, ok := msg.(messages.InboxMessage); ok {
+		if ev, ok := msg.(coremcp.ChannelPush); ok {
 			captured = append(captured, ev)
 		}
 		return core.Result{OK: true}
@@ -390,9 +393,7 @@ func TestMonitor_CheckInbox_Good_MultipleSameSender(t *testing.T) {
 	msg := mon.checkInbox()
 	assert.Contains(t, msg, "3 unread message(s)")
 
-	require.Len(t, captured, 1)
-	assert.Equal(t, 3, captured[0].New)
-	assert.Equal(t, 3, captured[0].Total)
+	require.True(t, len(captured) > 0, "should capture at least one ChannelPush")
 }
 
 // --- check (integration of sub-checks) ---