fix: restore anti-idle in manager.py, fix ENTRYPOINT quoting in Dockerfile

- manager.py: anti_idle_loop sends xdotool Shift to xfreerdp window every 30s
  while session is active; mousemove fallback if window not found
- Dockerfile: restore xdotool package; fix ENTRYPOINT JSON quoting lost in heredoc

rdp-proxy/manager.py

@@ -70,6 +70,35 @@ def _monitor_loop():
 
 
 threading.Thread(target=_monitor_loop, daemon=True).start()
+def _anti_idle_loop():
+    """Send Shift key every 30s while xfreerdp is connected to prevent screen lock."""
+    while True:
+        time.sleep(30)
+        with _lock:
+            active = _should_be_connected and _proc is not None and _proc.poll() is None
+        if not active:
+            continue
+        try:
+            # Try to send Shift to xfreerdp window
+            result = subprocess.run(
+                ["xdotool", "search", "--name", "FreeRDP", "key", "shift"],
+                env={**os.environ, "DISPLAY": DISPLAY},
+                capture_output=True, timeout=5,
+            )
+            if result.returncode != 0:
+                # Fallback: mousemove
+                subprocess.run(
+                    ["xdotool", "mousemove", "--sync", "960", "540"],
+                    env={**os.environ, "DISPLAY": DISPLAY},
+                    capture_output=True, timeout=5,
+                )
+        except Exception as e:
+            log.debug("anti_idle error: %s", e)
+
+
+threading.Thread(target=_anti_idle_loop, daemon=True).start()
+
+
 
 
 class Handler(BaseHTTPRequestHandler):