Flicker: print message about not showing output until completion

Improve shell command output handling

- Buffer shell command output to prevent terminal unresponsiveness
- Update display periodically (every second) for large outputs
- Add user notification about output buffering behavior
- Maintain truncation through terminal interface

This significantly improves the user experience when viewing large outputs
by preventing excessive screen updates. Note that due to OS-level output
buffering, shell commands won't show progress until completion.
Revert "try to fix buffering"

This reverts commit 9ccee4d26bab9267007760947f3c95bbb93a1fa2.
try to fix buffering
not sure
Try to best of both worlds

Author: endolith

interpreter/core/computer/terminal/terminal.py

@@ -163,8 +163,9 @@ def _streaming_run(self, language, code, display=False):
             else:
                 self._active_languages[language] = lang_class()
         try:
-            # Buffer for shell output - collect all output before displaying to prevent screen flicker
-            # Note: This means shell commands won't show progress until completion
+            # Buffer for shell output - collect output and update periodically to prevent terminal
+            # unresponsiveness with large outputs. Note: This means shell commands won't show
+            # progress until completion due to OS-level output buffering.
             shell_output = ""
 
             for chunk in self._active_languages[language].run(code):
@@ -187,6 +188,13 @@ def _streaming_run(self, language, code, display=False):
                     # For shell commands, buffer the output instead of streaming
                     # This prevents screen flicker with large outputs like 'type' or 'cat'
                     if language == "shell":
+                        # First shell command output - inform user about buffering
+                        if not shell_output:
+                            yield {
+                                "type": "console",
+                                "format": "output",
+                                "content": "Note: Shell command output will be shown after completion.\n\n"
+                            }
                         shell_output += chunk["content"]
                         continue