lang: replace stack-based parser with a recursive parser

lang/parse/eof.c

@@ -0,0 +1,7 @@
+#include "ctx.h"
+
+bool parse_eof(struct ivy_parser *parser)
+{
+	struct ivy_token *tok = peek_token(parser);
+	return (!tok && ivy_lexer_get_status(parser->p_src) == IVY_ERR_EOF);
+}