fix(cli): make refresh_interval configurable, default to 0 (disabled)

Commit 6724daa2c added refresh_interval=1.0 to keep the idle clock
ticking, but unconditional 1 Hz redraws in non-fullscreen prompt_toolkit
mode cause terminal emulators (Xshell, iTerm2, Windows Terminal) to
auto-scroll to the bottom on every tick — breaking scroll-up to read
history.

Drive it from display.cli_refresh_interval (0 = disabled, the default)
so users who want the ticking clock can opt in without affecting everyone.

Fixes: #48309
Related: 6724daa2c, 8972a151a

cli.py

@@ -13527,13 +13527,13 @@ class HermesCLI(CLIAgentSetupMixin, CLICommandsMixin):
             style=style,
             full_screen=False,
             mouse_support=False,
-            # The status bar contains wall-clock read-outs (live prompt elapsed
-            # and idle-since-last-turn). Once a turn finishes there may be no
-            # further events to invalidate the app, so prompt_toolkit would keep
-            # rendering the first post-turn value (usually ``✓ 0s``) forever.
-            # A low-rate refresh keeps the clock honest without reintroducing a
-            # custom repaint thread or touching conversation state.
-            refresh_interval=1.0,
+            # Read from display.cli_refresh_interval (default 0 = disabled).
+            # When non-zero, prompt_toolkit redraws the UI on this cadence
+            # during idle, keeping wall-clock status-bar read-outs ticking.
+            # Set to 0 to suppress background redraws entirely — avoids
+            # fighting terminal auto-scroll in non-fullscreen mode (Xshell,
+            # iTerm2, Windows Terminal). See #48309.
+            refresh_interval=float(CLI_CONFIG.get("display", {}).get("cli_refresh_interval", 0)),
             # Erase the live bottom chrome (status bar, input box, separator
             # rules) on exit instead of freezing a final copy into scrollback.
             # Without this, prompt_toolkit's render_as_done teardown repaints

hermes_cli/config.py

@@ -1581,6 +1581,12 @@ DEFAULT_CONFIG = {
         # TUI busy indicator style: kaomoji (default), emoji, unicode (braille
         # spinner), or ascii.  Live-swappable via `/indicator <style>`.
         "tui_status_indicator": "kaomoji",
+        # Seconds between prompt_toolkit redraws in the classic CLI when idle.
+        # 0 = disabled (no background refresh — the pre-0.15.2 behaviour).
+        # Positive values e.g. 1.0 keep wall-clock status-bar read-outs
+        # (idle-since-last-turn) ticking but may fight terminal auto-scroll in
+        # non-fullscreen mode on some emulators (Xshell, iTerm2, etc.).
+        "cli_refresh_interval": 0,
         "user_message_preview": {  # CLI: how many submitted user-message lines to echo back in scrollback
             "first_lines": 2,
             "last_lines": 2,