Phase 20.34: expand MirBuilder internal library with comprehensive lowering boxes; add pattern registry and program scanning infrastructure; implement internal lowerers for if/loop/return patterns; add dev tools and comprehensive canary tests; update VM boxes and host providers for internal delegation; wire phase2034 test suite with 30+ canary scripts covering internal lowering scenarios

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

src/runtime/plugin_loader_v2/enabled/extern_functions.rs

@@ -214,7 +214,11 @@ fn handle_codegen(method_name: &str, args: &[Box<dyn NyashBox>]) -> BidResult<Op
             let nyrt = std::env::var("NYASH_EMIT_EXE_NYRT").ok().map(std::path::PathBuf::from);
             let opts = crate::host_providers::llvm_codegen::Opts { out, nyrt, opt_level, timeout_ms: None };
             match crate::host_providers::llvm_codegen::mir_json_to_object(&mir_json, opts) {
-                Ok(p) => Ok(Some(Box::new(StringBox::new(&p.to_string_lossy())) as Box<dyn NyashBox>)),
+                Ok(p) => {
+                    // Convert PathBuf → String via lossy conversion (owned)
+                    let s = p.to_string_lossy().into_owned();
+                    Ok(Some(Box::new(StringBox::new(s)) as Box<dyn NyashBox>))
+                },
                 Err(_e) => Ok(None),
             }
         }