fix: auto-detect missing TTY and fall back to auto mode

When stdin has no TTY (Docker without -it), IntPrompt/Confirm raise
EOFError and crash the container into a restart loop. Treat a non-TTY
stdin the same as AUTO_MODE=true so headless runs work without any env
var configuration.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

winnow/cli.py

@@ -2,6 +2,7 @@
 
 import logging
 import os
+import sys
 
 from rich import print as rprint
 from rich.prompt import Confirm
@@ -63,15 +64,19 @@ def main() -> None:
             rprint("[bold red]Could not fetch people from Immich. Check URL/Key.[/bold red]")
             return
 
-        # Check for non-interactive mode
+        # Check for non-interactive mode; also force auto when stdin has no TTY
-        auto_mode = os.environ.get("AUTO_MODE", "false").lower() == "true"
+        # (e.g. Docker without -it) to avoid an EOFError crash
+        auto_mode = os.environ.get("AUTO_MODE", "false").lower() == "true" or not sys.stdin.isatty()
         dry_run = os.environ.get("DRY_RUN", "false").lower() in ("true", "1", "yes")
 
         if dry_run:
             rprint("[bold yellow]DRY RUN — no images will be downloaded or uploaded[/bold yellow]")
 
         if auto_mode:
-            rprint("[bold cyan]Running in AUTO mode (non-interactive)[/bold cyan]")
+            if not sys.stdin.isatty() and os.environ.get("AUTO_MODE", "false").lower() != "true":
+                rprint("[dim]No TTY detected — running in auto mode. Set AUTO_MODE=true to suppress this.[/dim]")
+            else:
+                rprint("[bold cyan]Running in AUTO mode (non-interactive)[/bold cyan]")
             jobs = auto_configure(people)
         else:
             jobs = interactive_configure(people)