- Add z_rt_default.go with signal handler for SIGSEGV on non-wasm platforms - Convert segmentation faults from nil pointer access to Go panic - Enable recover() to catch nil pointer dereference errors - Use build tag (!wasm) to maintain wasm platform compatibility - Remove commented-out signal handling code from z_rt.go This aligns llgo's behavior with standard Go, where accessing nil pointer fields triggers a recoverable panic instead of immediate program crash. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>