Preserve advanced fan mode across user mode changes

[DKalimist]

Root cause

Operate::setUserMode() unconditionally forces fan_mode back to auto,
regardless of whether advanced/custom fan control is active.

On startup, MainWindow::loadConfigs() calls operate.loadSettings()
(which correctly restores UserMode first, then fanModeAdvanced last -
ending in advanced mode), immediately followed by updateUserMode(). That
function calls radioButton->click() to sync the UI, which fires the
button's toggled signal and re-enters setUserMode() as a side effect -
silently dropping advanced mode back to auto right after it was restored.

The same happens any time the shift/user mode changes while advanced is
active, not just at startup.

Confirmed at the raw EC register level (fan curve arrays stay correctly
loaded at their addresses, only fan_mode gets reset).

Fix

Skip the fan_mode write in setUserMode() when advanced mode is already
active, unless the target mode is silent_mode (which intentionally
forces silent fan mode on purpose).

Testing

Built from source, reproduced the bug pre-patch (fresh launch with
fanModeAdvanced=true saved always came up in auto). Post-patch, tested
two independent cold launches: fan_mode comes up and stays advanced
automatically, curve values unchanged, no manual re-toggle needed.

Fixes #246

[mahdishariatzade]

Tested PR #327 successfully on a real MSI Stealth 14 Studio A13VF.

Environment:

Ubuntu 26.04 LTS
Kernel 7.0.0-29-generic
MControlCenter 0.5.1 baseline
msi-ec kernel module

Before this patch, enabling Advanced Fan mode worked initially, but starting MControlCenter or changing the Shift/User Mode silently changed fan_mode from advanced back to auto. The saved fanModeAdvanced=true setting was therefore not reliably preserved.

Built and installed this PR from commit cbdba55 and verified:

MControlCenter starts with Advanced Fan mode preserved.
Changing Shift Mode (e.g. Turbo -> Comfort) keeps fan_mode=advanced.
Closing MControlCenter does not reset Advanced Fan mode.
After reboot, with fanModeAdvanced=true saved in ~/.config/MControlCenter.conf, Advanced Fan mode is restored correctly.
The custom fan curve continues to operate correctly.

The built binaries matched the installed binaries by SHA-256 after installation, confirming that the PR build was the version being tested.

This fixes the issue for my hardware/configuration. Thanks!

[Valarck82]

Working wonderfully, thank you so much.

Cachyos
kernel: 7.2.0