Added tons of opcode documentation, changed license to ISC and a lot of file refactoring.

src/vm/arrays/arr_set.c

@@ -1,3 +1,37 @@
+/**
+ * This file is part of the Fun programming language.
+ * https://hanez.org/project/fun/
+ *
+ * Copyright 2025 Johannes Findeisen <you@hanez.org>
+ * Licensed under the terms of the ISC license.
+ * https://opensource.org/license/isc-license-txt
+ */
+
+/**
+* @file arr_set.c
+ * @brief Implements the OP_ARR_SET opcode for setting elements in arrays in the VM.
+ *
+ * This file handles the OP_ARR_SET instruction, which sets a value at a specified index in an array.
+ * The value, index, and array are popped from the stack, and the value is pushed back onto the stack.
+ *
+ * Behavior:
+ * - Pops the value, index, and array from the stack.
+ * - Sets the value at the specified index in the array.
+ * - Pushes the value back onto the stack.
+ *
+ * Error Handling:
+ * - Exits with an error if the array or index is of the wrong type.
+ * - Exits with an error if the index is out of bounds.
+ *
+ * Example:
+ * // Bytecode: OP_ARR_SET
+ * // Stack before: [42, 1, [10, 20, 30]]
+ * // Stack after: [42]
+ *
+ * @author Johannes Findeisen
+ * @date 2025-10-16
+ */
+
 case OP_ARR_SET: {
     Value v = pop_value(vm);
     Value idx = pop_value(vm);