chore: import upstream snapshot with attribution

surfaces/interactive_shell/runtime/startup/initial_input.py

@@ -0,0 +1,54 @@
+"""Non-interactive initial-input replay for REPL startup."""
+
+from __future__ import annotations
+
+from rich.console import Console
+
+from platform.analytics.repl_context import bound_repl_turn_context
+from surfaces.interactive_shell.session import Session
+from surfaces.interactive_shell.ui.banner import render_banner
+from surfaces.interactive_shell.ui.input_prompt.rendering import render_submitted_prompt
+from surfaces.interactive_shell.utils.telemetry import PromptRecorder
+
+_TURN_KIND = "agent"
+
+
+def run_initial_input(
+    initial_input: str,
+    session: Session,
+) -> int:
+    # Imported lazily so importing this module during REPL boot (main.py imports
+    # ``run_initial_input`` at top) does not pull the harness/turn-execution
+    # stack into the base import path when there is no initial input to replay.
+    from surfaces.interactive_shell.runtime.shell_turn_execution import execute_shell_turn
+
+    console = Console(
+        highlight=False,
+        force_terminal=True,
+        color_system="truecolor",
+        legacy_windows=False,
+    )
+    render_banner(console)
+    for line in initial_input.splitlines():
+        stripped = line.strip()
+        if not stripped:
+            continue
+        render_submitted_prompt(console, session, stripped)
+        recorder = PromptRecorder.start(session=session, text=stripped, turn_kind=_TURN_KIND)
+        with bound_repl_turn_context(
+            session_id=session.session_id,
+            turn_kind=_TURN_KIND,
+            prompt_turn_id=recorder.turn_id if recorder is not None else None,
+        ):
+            execute_shell_turn(
+                stripped,
+                session,
+                console,
+                recorder=recorder,
+                confirm_fn=None,
+                is_tty=False,
+            )
+    return 0
+
+
+__all__ = ["run_initial_input"]