[ALL] Add more functionality to Input<name>() callback in VScript

[main-thing]

Description

This PR aims to add more functionality to the Input<name>() callback.

This PR adds the following functionality:

• a new variable input_value that stores the parameter of the input.
• activator and caller can be reassigned within the function.

Example:

local temp = SpawnEntityFromTable("info_target", {targetname = "entity_1"})
local test_ent = SpawnEntityFromTable("info_target", {targetname = "entity_2"})
test_ent.ValidateScriptScope()
test_ent.GetScriptScope().Inputrunscriptcode <- function()
{
	printf("Input Value: %s\n", input_value)
	printf("Initial Activator: %s\n", activator.GetName())
	activator = self
	caller = self
	return true
}

test_ent.AcceptInput("runscriptcode", "printf(`Current Activator: %s\n`, activator.GetName())", temp, temp)
temp.Destroy()
test_ent.Destroy()

/* Console output:
] script_execute input_remap_test
Input Value: printf(`Current Activator: %s`, activator.GetName())
Initial Activator: entity_1
Current Activator: entity_2
*/