fix: Agent retries transient transport errors/proxy 5xx with backoff (classify, complete, fail); hide console behind the GUI wizard; 1.2.2

Found in the clean-Windows recovery test: a single TLS handshake failure mid-job failed a whole sync.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

installer/setup_main.py

@@ -364,6 +364,17 @@ def cli() -> int:
     return 0
 
 
+def _hide_console():
+    """The frozen Setup is a console-subsystem exe (needed for --cli); in GUI mode the black console window behind the wizard is noise, so hide it."""
+    try:
+        import ctypes
+        handle = ctypes.windll.kernel32.GetConsoleWindow()
+        if handle:
+            ctypes.windll.user32.ShowWindow(handle, 0)
+    except Exception:  # noqa: BLE001 - cosmetic only
+        pass
+
+
 def main():
     if "--cli" in sys.argv:
         try:
@@ -371,6 +382,7 @@ def main():
         except RuntimeError as error:
             print(f"INSTALL_FAIL {error}", file=sys.stderr)
             return 1
+    _hide_console()
     root = tk.Tk()
     SetupWizard(root)
     root.mainloop()