[Pre-release 2.7.10] Non-interactive `ssh host <command>` hangs under mirrored networking (OpenSSH IPQoS mid-session retag)

### Windows Version
Microsoft Windows [Version 10.0.26200.8655]

### WSL Version
2.7.10.0 (pre-release)

```
WSL version: 2.7.10.0
Kernel version: 6.18.33.2-2
WSLg version: 1.0.73.2
MSRDC version: 1.2.6676
Direct3D version: 1.611.1-81528511
DXCore version: 10.0.26100.1-240331-1435.ge-release
Windows version: 10.0.26200.8655
```

### Are you using WSL 1 or WSL 2?
- [x] WSL 2
- [ ] WSL 1

### Kernel Version
6.18.33.2-2 (`6.18.33.2-microsoft-standard-WSL2`)

### Distro Version
Debian GNU/Linux 13 (trixie)

### Other Software
- OpenSSH_10.0p2 Debian-7+deb13u4 (client inside WSL)
- `.wslconfig` uses mirrored networking:

```ini
[wsl2]
networkingMode=mirrored
firewall=false
dnsTunneling=false
autoProxy=false
```

- Active NIC at time of repro: Intel Wi-Fi 6 AX201 (also reproduced to LAN host)
- No HP “LiveQoS” NDIS filter present; Microsoft QoS Packet Scheduler (`ms_pacer`) is enabled

### Repro Steps
1. Install **WSL pre-release 2.7.10.0** with `networkingMode=mirrored`.
2. From WSL, use stock OpenSSH defaults (`ssh -G ` reports `ipqos ef cs1`).
3. Interactive login works:

```bash
ssh
```

4. Any non-interactive remote command hangs after authentication:

```bash
ssh true
ssh 'echo ok'
ssh -T true
```

5. Same hang occurs to LAN hosts and to hosts reached via public DNS/WAN.
6. Workaround restores remote commands:

```bash
ssh -o IPQoS=none true
# or in ~/.ssh/config:
# Host *
# IPQoS none
```

7. **Does not reproduce** in either of these controls (same hosts / same style of non-interactive command):
- **Non-WSL** (native Windows / non-WSL SSH): `ssh ` works.
- **Non-pre-release / stable WSL** (same distro/OpenSSH settings/hosts): `ssh ` works.

Failure is specific to **WSL pre-release 2.7.10.0** in this environment.

### Expected Behavior
`ssh ` should complete normally (auth, exec, exit), same as interactive `ssh `.

### Actual Behavior
- Interactive `ssh ` succeeds.
- Non-interactive `ssh ` authenticates, then hangs indefinitely (no command output, no exit).
- `ssh -vvv` shows the session stalls after sending the exec request with channel receive window stuck at 0, e.g. `open confirm rwindow 0`, and never receives a window adjust / exit-status.
- Immediately after the command channel is set up, the client switches QoS (`set_sock_tos` / non-interactive path). OpenSSH default is interactive **EF**, bulk/non-interactive **CS1** (`IP_TOS 0x20`), with a **mid-session retag** when the session becomes non-interactive (OpenSSH/Debian IPQoS updates in 1:10.0p1-7+deb13u3+).

### Diagnostic Logs
**Theory:** WSL pre-release mirrored networking mishandles OpenSSH’s mid-connection DSCP/TOS change (EF → CS1). Interactive sessions never take the bulk retag path, so they keep working. Stable WSL does not show this failure.

**Workaround:** `IPQoS none` (or a single fixed class such as `IPQoS ef` / `IPQoS af21`) so OpenSSH does not retag mid-session.

Happy to gather Feedback Hub / networking logs if useful.

Reproduce the hang with mirrored networking using `ssh -vvv` and compare the pre-release behavior with stable WSL, focusing on the EF-to-CS1 IPQoS transition described in the report. The fix is complete when non-interactive SSH commands finish with default IPQoS while interactive sessions and the listed controls continue to work.

Written by the indexing model from the issue text.