Dragging a connection from the input port in a visual shader results in an error

[YuriSizov]

Tested versions

Reproduceable on master at 1952f64.

System information

Godot v4.3.dev (1952f64) - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 3070 Ti Laptop GPU (NVIDIA; 31.0.15.3742) - 12th Gen Intel(R) Core(TM) i7-12700H (20 Threads)

Issue description

Dragging a new connection from an input port and dropping it to create a new node results in an error in the visual shader plugin.

ERROR: Condition "!shader_rid.is_valid()" is true. Returning: 0
   at: VisualShaderNodeParameterRef::get_parameters_count (scene\resources\visual_shader.cpp:3605)
scene\resources\visual_shader.cpp:3605 - Condition "!shader_rid.is_valid()" is true. Returning: 0

I couldn't reproduce this by dragging from an output port. Also, on a few occasions there was no error even for the input port, but otherwise it was reliably reproduceable.

Steps to reproduce

godot.windows.editor.dev.x86_64_2024-01-18_15-10-26.mp4

Minimal reproduction project (MRP)

N/a