Fix multi-line system messages; add message height logging

ober

ce9d86f98781efc9639588d08353f3ed8966a860

diff --git a/src/jcode/ui/tui-message.ss b/src/jcode/ui/tui-message.ss
index 8c16a21..c1dfa18 100644
--- a/src/jcode/ui/tui-message.ss
+++ b/src/jcode/ui/tui-message.ss
@@ -139,7 +139,8 @@
   (list (list (cons (string-append "Error: " content) 'error))))
 
 (def (render-system-content content)
-  (list (list (cons content 'dim))))
+  (map (lambda (line) (list (cons line 'dim)))
+       (string-split content #\newline)))
 
 (def (tool-summary tool-name metadata)
   (cond
diff --git a/src/jcode/ui/tui.ss b/src/jcode/ui/tui.ss
index 2f4ca88..0a32cc8 100644
--- a/src/jcode/ui/tui.ss
+++ b/src/jcode/ui/tui.ss
@@ -560,6 +560,9 @@
 
 (def (add-message! state msg)
   (reflow-message! msg (msg-area-width state))
+  (tui-log "add-message: role=~a height=~a lines=~a width=~a"
+           (msg-block-role msg) (msg-block-height msg)
+           (length (msg-block-lines msg)) (msg-area-width state))
   (app-state-messages-set! state
     (append (app-state-messages state) (list msg))))