Disable WLAN AutoConfig during streaming to eliminate Wi-Fi jitter

[psykokwak-com]

Summary

• Disables WLAN AutoConfig (wlan_intf_opcode_autoconf_enabled) during streaming to prevent Windows from performing periodic background Wi-Fi scans that cause 50-400ms latency spikes every ~30 seconds
• Re-enables AutoConfig explicitly in exitLowLatencyMode() before closing the WLAN handle, ensuring network discovery is fully restored after streaming
• Adds error logging for the existing media streaming mode WlanSetInterface call

Problem

On Windows, the WLAN AutoConfig service performs cyclic background scans at ~30-second intervals, even when already connected to a network. These scans cause periodic latency spikes of 50-400ms that are
clearly visible as jitter during game streaming over Wi-Fi.

The existing wlan_intf_opcode_media_streaming_mode optimization does not prevent these scans on all drivers (e.g., Intel AX211 returns ERROR_NOT_SUPPORTED (50) for media streaming mode).

Running netsh wlan set autoconfig enabled=no interface="Wi-Fi" before streaming completely eliminates the jitter. This PR implements the programmatic equivalent using WlanSetInterface with
wlan_intf_opcode_autoconf_enabled.

Testing

Tested on a laptop with Intel AX211 Wi-Fi adapter streaming at 2560x1600@165Hz over Wi-Fi 6:

• Before: periodic latency spikes of 50-400ms every ~30s visible in network statistics
• After: Frames dropped due to network jitter: 0.00%, average network latency 2ms

Log output confirms the fix is active:
WLAN interface 0 failed to enter low latency mode (error 50)
WLAN interface 0 cyclic background scan disabled
[...]
WLAN interface 0 cyclic background scan re-enabled

Notes

• Uses the same WlanSetInterface API and dynamic loading pattern already in place for media streaming mode
• No new DLL dependencies — wlan_intf_opcode_autoconf_enabled is part of the same wlanapi.dll API
• AutoConfig is restored both explicitly (before handle close) and implicitly (when the WLAN handle is closed by the OS)
• Requires the application to run with elevated privileges (administrator) for the autoconfig disable to succeed