Bug 512549

SUMMARY
(hardware: Asus Zenbook Flip UP3404VA, bundled "Asus Pen 2.0")
When trying to use the stylus, the cursor will follow where the pen is (both ~2cm from screen and touching), but when pressing the screen, nothing happens on applications (Rnote, Krita + anything with a button)  

STEPS TO REPRODUCE
1. Open into a session
2. Open any app like firefox, krita, and try and use the stylus

OBSERVED RESULT
Cursor moves fine, actual press events don't seem to get forwarded to the application and thus canvas draws in krita, button presses in firefox etc don't register

EXPECTED RESULT
Presses in e.g. firefox trigger the button
Strokes in e.g. krita are sent to krita, registered, drawn etc

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Kernel is 6.14.0-35-generic 64bit
KDE Plasma Version: 6.5.2
KDE Frameworks Version: 6.19.0
Qt Version: 6.9.3

ADDITIONAL INFORMATION
output of `sudo libinput debug-events`, testing the stylus briefly, truncated for what seems important (full log is attached)
```
[...]
-event7   DEVICE_ADDED                 WDHT1F01:00 2575:0916 Stylus      seat0 default group9  cap:T  size 301x188mm left calib
[...]
 event7   TABLET_TOOL_AXIS             +0.002s          229.18*/150.76* tilt: 0.00/0.00 pressure: 0.00
[...]
 event7   TABLET_TOOL_PROXIMITY        +0.395s          232.06*/149.74* tilt: 0.00*/0.00*       pressure: 0.00* pen      (0, id 0xc2) proximity-in      axes:pt btn:S
[...]
 event7   TABLET_TOOL_TIP              +0.489s          232.44*/153.14* tilt: 8.78*/11.66*      pressure: 0.55* down
[...]
 event7   TABLET_TOOL_AXIS             +0.500s          232.44/153.14   tilt: 8.78/11.67*       pressure: 0.55
[...]
 event7   TABLET_TOOL_AXIS             +0.500s          232.44/153.14   tilt: 8.78/11.67*       pressure: 0.55
[...]
 event7   TABLET_TOOL_TIP              +0.590s          233.98*/153.16  tilt: 0.00*/0.00*       pressure: 0.00* up
[...]
 event7   TABLET_TOOL_AXIS             +0.591s          234.00*/153.17* tilt: 0.00/0.00 pressure: 0.00
[...]
 event7   TABLET_TOOL_PROXIMITY        +0.653s          233.92/153.06   tilt: 0.00/0.00 pressure: 0.00  pen      (0, id 0xc2) proximity-out
```
so libinput seems to be okay, it does actually detect pen down events and outputs pressure+tilt 

output of `cat ~/.config/kcminputrc`:
```
amenaijp@amenaijp-zenbook:~$ cat ~/.config/kcminputrc
[ButtonRebinds][Tablet][Wacom Intuos BT M Pad]
0=Key,Ctrl+Z

[Libinput][1267][12737][ASUE120C:00 04F3:31C1 Mouse]
PointerAcceleration=-0.600
PointerAccelerationProfile=1

[Libinput][1267][12737][ASUE120C:00 04F3:31C1 Touchpad]
DisableWhileTyping=false
Enabled=true
NaturalScroll=true
TapAndDrag=false
```

The inbuilt tablet tester in krita and the tablet tester in System Settings detect nothing, however, if I press a certain one of the two available buttons on the stylus while trying to draw something, both tablet testers detect stylus input as expected (though they don't detect the initial button press)

On windows, the stylus is detected only as mouse movement (per krita tablet tester) but one of the buttons does do a special ring around the cursor when I press it so the hardware seems okay and I'm attributing that to general win11 jankiness 

The stylus did work okay a few months ago so the issue might be caused by a regression

Thank you!