[php-src] PR #25352: Fix truncated anonymous class names in error messages and logs

Pull Request: https://github.com/php/php-src/pull/25352 Author: jorgsowa I detected this problem while working on PHP Parser in Rust. Anonymous class names contain a NUL byte (class@anonymous\0file:line$0). Since the %pS migration (#23142), some error messages include the full name, which exposed two problems: 1. Messages cut off in output. php_error_cb() still wrote the message as a C string in the error log, the HTML fatal error output and the XML-RPC fault, so it stopped at the NUL: PHP Fatal error: Class class@anonymous in Standard input code on line 2 The log now writes NUL bytes as \0 (log sinks take C strings), and the HTML/XML-RPC output prints the message by length. 2. Inconsistent names. Messages not covered by the migration still printed the short name via ZSTR_VAL() / ZEND_FN_SCOPE_NAME(), sometimes both forms in one message: Class class@anonymous\0…:2$0 must implement 1 abstract method (class@anonymous::$p::get) These now use %pS: inheritance errors (abstract method list, #[\Override], access level, static/abstract), private method/destructor calls, private(set) and readonly modification, return type, too few arguments, by-ref unpacking, virtual property unserialization, DOMXPath::__construct() reentry and XMLReader readonly properties. ext/filter is covered by #23155.