Setting shader parameter to const array causes error when material is freed

### Tested versions

- Reproducible in: v4.3.stable.steam [77dcf97d8], v4.4.dev2.official [97ef3c837], v4.0.stable.official [92bee43ad]
- Not reproducible in: v2.1.stable.official, v3.0.stable.official, v3.5.1.stable.official [6fed1ffa3]

### System information

Godot v4.3.stable (77dcf97d8) - Windows 10.0.22631 - Vulkan (Mobile) - integrated Intel(R) Iris(R) Xe Graphics (Intel Corporation; 31.0.101.5186) - 13th Gen Intel(R) Core(TM) i7-1360P (16 Threads)

### Issue description

If a shader parameter on a material is set to an array that is declared as const, the engine erroneously attempts to clear the array when the material is freed. This results in an error in the debugger tab, "clear: Array is in read-only state". In the MRP, I achieved this with the following code:

```gdscript
const TEST_CONST = []

func _ready() -> void:
var new_node = Node2D.new()
new_node.material = ShaderMaterial.new()
new_node.material.set_shader_parameter("test", TEST_CONST)
new_node.queue_free()
```

### Steps to reproduce

Run the minimal reproduction project and check the debugger tab.

### Minimal reproduction project (MRP)

[clearbug.zip](https://github.com/user-attachments/files/17091629/clearbug.zip)

Start with the clearbug.zip minimal reproduction and the _ready() sequence that assigns TEST_CONST through ShaderMaterial.set_shader_parameter() before calling queue_free(). Reproduce the debugger error, then trace the material-freeing path to identify why the const array is cleared. Done means freeing the material no longer reports "Array is in read-only state".

Written by the indexing model from the issue text.