windows: retry the first start instead of hiding a Steam setting

The 'Unable to initialize Steam' box comes from the server's first start after
an install, with or without Steam running; the registry workaround was not the fix.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

README.md

@@ -68,7 +68,7 @@ More for players (Steam and non-Steam): [docs/PLAYERS.md](docs/PLAYERS.md).
 
 - **Setup stopped with an error.** Fix what it says (usually the internet connection) and run it again. It continues where it stopped.
 - **Friends can't connect, but you can.** On Windows, run `cs.cmd` → 10 → 1 and accept the admin prompt so the firewall lets them in. If they're not in your house, check the playit tunnel or the port forward.
-- **"Unable to initialize Steam" (Windows).** Start the server from `cs.cmd`, not by opening `hlds.exe` directly.
+- **"Unable to initialize Steam" (Windows).** This can happen once, on the first start after installing; `cs.cmd` and setup retry by themselves. If you started `hlds.exe` yourself, close the box and start the server with `cs.cmd` → 9.
 - **The server window closes right away, or setup says files are missing.** Your antivirus probably removed a file. Allow the install folder in it and run `setup.cmd` again.
 - **The port is taken.** Setup offers the next free port. Your friends then need that port in the address.