[BUG] MIDI Program Change Commands Not Responding in CONTROL Input Plugins

[Riebeck-one]

Describe the bug
There are several issues with MIDI Program Change (PC) commands when controlling plugins with CONTROL input ports.

To Reproduce
Steps to reproduce the behavior:

1. Insert a plugin that has a CONTROL INPUT port.
2. Link the plugin to a MIDI device.
3. Send MIDI PC commands from the MIDI device.
4. The plugin does not respond to the MIDI program changes.
5. Enabling the midi-input node makes the plugin respond to the MIDI program changes, even though it's not connected to it.

Expected behavior
Plugins should change their MIDI program when PC commands are received.

Screenshots

Report.mp4

Element version
Latest Git version

Desktop (please complete the following information):

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                 .o+`                    ---------------
                `ooo/                    OS: Arch Linux x86_64
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              `+oooooo:                  Kernel: Linux 6.11.0-1-cachyos
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                                         GPU: AMD Radeon RX 7900 XTX [Discrete]
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                                         Local IP (enp38s0): 192.168.50.214/24
                                         Locale: fr_FR.UTF-8

Standalone or Plugin
This issue occurs in the standalone version.

[mfisher31]

Thanks for the detailed report on this. Will check it out as soon as I can.