[php-src] PR #25182: Fix GH-25165: Tracing JIT spins once the JIT buffer is full

Pull Request: https://github.com/php/php-src/pull/25182 Author: iliaal Once the JIT buffer is full, zend_jit_blacklist_trace_exit() marks a side exit blacklisted even though it could not emit the exit stub, so the exit stays unlinked and every later hit returned 0 from zend_jit_trace_exit(). When that exit's opline is the root trace's start, resuming there re-enters the same trace and the process spins at 100% CPU. Returning 1 in that case runs the original handler, the same guard zend_jit_trace_exit_to_vm() applies when it can emit a stub. The commit also backports dstogov/ir#295, which frees the DynASM state when the code buffer is full; without it, debug builds report a leak in the new test. Reproduced on PHP-8.4 and master debug builds, hybrid and CALL VM. Fixes GH-25165