feat(search): align conversation identity search

internal/search/engine.go

@@ -142,12 +142,13 @@ func timestampPtr(value *int64) int64 {
 
 func ConversationDocument(conv model.Conversation) SearchDocument {
 	inboxID := conv.InboxID
+	content := conversationSearchContent(conv)
 	doc := SearchDocument{
 		ID:               conv.ID,
 		Type:             ResultTypeConversation,
 		AccountID:        conv.AccountID,
-		Title:            fmt.Sprintf("Conversation #%d", conv.ID),
-		Content:          conv.Labels,
+		Title:            conversationSearchTitle(conv),
+		Content:          content,
 		Status:           conv.Status,
 		Priority:         conv.Priority,
 		Labels:           splitLabels(conv.Labels),
@@ -165,6 +166,24 @@ func ConversationDocument(conv model.Conversation) SearchDocument {
 	return doc
 }
 
+func conversationSearchTitle(conv model.Conversation) string {
+	if conv.DisplayID != nil && *conv.DisplayID != 0 {
+		return fmt.Sprintf("Conversation #%d", *conv.DisplayID)
+	}
+	return fmt.Sprintf("Conversation #%d", conv.ID)
+}
+
+func conversationSearchContent(conv model.Conversation) string {
+	parts := make([]string, 0, 5)
+	if conv.DisplayID != nil && *conv.DisplayID != 0 {
+		parts = append(parts, fmt.Sprintf("%d", *conv.DisplayID))
+	}
+	if conv.Contact != nil {
+		parts = append(parts, conv.Contact.Name, conv.Contact.Email, conv.Contact.PhoneNumber, conv.Contact.Identifier)
+	}
+	return strings.TrimSpace(strings.Join(parts, " "))
+}
+
 func MessageDocument(msg model.Message) SearchDocument {
 	inboxID := msg.InboxID
 	conversationID := msg.ConversationID

internal/search/engine_test.go

@@ -48,6 +48,9 @@ func TestDocumentBuildersSetStableUIDAndType(t *testing.T) {
 	conv.InboxID = 7
 	conv.ContactID = 9
 	conv.LastActivityAt = &lastActivity
+	displayID := uint(42)
+	conv.DisplayID = &displayID
+	conv.Contact = &model.Contact{Name: "Ada Lovelace", Email: "ada@example.com", PhoneNumber: "+123", Identifier: "ada-id"}
 	doc := ConversationDocument(conv)
 
 	assert.Equal(t, "3:conversation:12", doc.UID)
@@ -55,6 +58,8 @@ func TestDocumentBuildersSetStableUIDAndType(t *testing.T) {
 	assert.Equal(t, uint(3), doc.AccountID)
 	assert.Equal(t, []string{"billing", "urgent"}, doc.Labels)
 	assert.Equal(t, lastActivity, doc.LastActivityAtTS)
+	assert.Equal(t, "Conversation #42", doc.Title)
+	assert.Equal(t, "42 Ada Lovelace ada@example.com +123 ada-id", doc.Content)
 }
 
 func TestContactDocumentSetsResolvedScopeFields(t *testing.T) {