Midi control messages are delayed

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### System Information

OpenSUSE Tumbleweed

### LMMS Version(s)

1.2.2 (flatpak), 1.3.0~git2024.09.21-1.3 (repo-oss)

### Most Recent Working Version

_No response_

### Bug Summary

when using my midi keyboard (AKAI MPK49) LMMS controls do not correctly process control messages, always leaving a single message "queued" and only processing that message when a new message enters that "queue" or some other event triggers processing of midi control messages.
this results in, for example:

- buttons inverting their behaviour
- knobs and sliders sticking to the last value received before the intended value. this is particularly annoying when trying to zero or max a control.

additionally, certain other events will partially trigger processing:

- hovering certain buttons (mute, solo) will cause them to process the message
- other controls depending on that particular control will not be updated (hovering solo will update solo but not the mute buttons it normally toggles)

minor details:

- i have used drumstick midi monitor to verify the proper reception of midi control messages.
- notes do not display this issue. it only affects control messages.

### Expected Behaviour

controls process midi control messages as they arrive.

### Steps To Reproduce

1. use a midi keyboard
2. map a keyboard control to an LMMS control
3. try to use it, it will always display the second-last value received by LMMS

### Logs

Click to expand

### Screenshots / Minimum Reproducible Project

_No response_

### Please search the issue tracker for existing bug reports before submitting your own.

- [X] I have searched all existing issues and confirmed that this is not a duplicate.

Reproduce the issue in LMMS with an AKAI MPK49 or another MIDI keyboard, mapping a control and comparing control messages with notes. Trace the MIDI control-message handling from input receipt to LMMS control updates. Done means each arriving control message is processed immediately, without requiring a subsequent message or UI event.

Written by the indexing model from the issue text.