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

src/vm/core/call.c

@@ -1,3 +1,32 @@
+/**
+ * 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 call.c
+ * @brief Implements the OP_CALL opcode for function calls in the VM.
+ *
+ * This file handles the OP_CALL instruction, which calls a function with arguments.
+ *
+ * Behavior:
+ * - operand specifies number of arguments
+ * - Pops args and function from stack
+ * - Creates new frame with args in locals
+ * - Sets IP to start of function
+ *
+ * Error Handling:
+ * - Exits with error if not enough args
+ * - Exits if function isn't callable
+ *
+ * @author Johannes Findeisen
+ * @date 2025-10-16
+ */
+
 case OP_CALL: {
     int argc = inst.operand;
     if (argc < 0) argc = 0;