Add debug logging to diagnose CI crash location

Adding eprintln statements to track:
- Thread ID for ThreadScope new/drop
- Each step in spawn_blocking closure
- Each estrdup call

This will help identify exactly where the crash occurs in CI.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: Qard

src/embed.rs

@@ -41,9 +41,7 @@ impl Drop for BlockingTaskHandle {
         if let Some(handle) = guard.take() {
           // Use block_on to wait for the task to complete
           // This ensures ThreadScope::drop() runs and PHP TLS is cleaned up
-          let _ = crate::sapi::fallback_handle().block_on(async move {
-            let _ = handle.await;
-          });
+          let _ = crate::sapi::fallback_handle().block_on(handle);
         }
       }
     }
@@ -343,31 +341,43 @@ impl Handler for Embed {
 
     // Spawn blocking PHP execution - ALL PHP operations happen here
     let blocking_handle = tokio::task::spawn_blocking(move || {
+      eprintln!("[DEBUG] spawn_blocking: starting");
       // Keep sapi alive for the duration of this task
       let _sapi = _sapi;
+      eprintln!("[DEBUG] spawn_blocking: creating ThreadScope");
       let _thread_scope = ThreadScope::new();
+      eprintln!("[DEBUG] spawn_blocking: ThreadScope created");
 
       // Setup RequestContext (always streaming from SAPI perspective)
       // RequestContext::new() will extract the request body's read stream and add it as RequestStream extension
+      eprintln!("[DEBUG] spawn_blocking: creating RequestContext");
       let ctx = RequestContext::new(
         request,
         docroot.clone(),
         response_writer.clone(),
         headers_sent_tx,
       );
+      eprintln!("[DEBUG] spawn_blocking: setting RequestContext::current");
       RequestContext::set_current(Box::new(ctx));
+      eprintln!("[DEBUG] spawn_blocking: RequestContext set");
 
       // All estrdup calls MUST happen here, inside spawn_blocking, after ThreadScope::new()
       // has initialized PHP's memory manager for this thread.
       // These will be freed by efree in sapi_module_deactivate during request shutdown.
+      eprintln!("[DEBUG] spawn_blocking: calling estrdup for request_uri_str");
       let request_uri_c = estrdup(request_uri_str.as_str());
+      eprintln!("[DEBUG] spawn_blocking: calling estrdup for path_translated");
       let path_translated = estrdup(translated_path_str.as_str());
+      eprintln!("[DEBUG] spawn_blocking: calling estrdup for request_method");
       let request_method = estrdup(method_str.as_str());
+      eprintln!("[DEBUG] spawn_blocking: calling estrdup for query_string");
       let query_string = estrdup(query_str.as_str());
+      eprintln!("[DEBUG] spawn_blocking: calling estrdup for content_type");
       let content_type = content_type_str
         .as_ref()
         .map(|s| estrdup(s.as_str()))
         .unwrap_or(std::ptr::null_mut());
+      eprintln!("[DEBUG] spawn_blocking: estrdup calls complete");
 
       // Prepare argv pointers
       let argc = args.len() as i32;

src/scopes.rs

@@ -20,18 +20,24 @@ pub(crate) struct ThreadScope();
 
 impl ThreadScope {
   pub fn new() -> Self {
+    let thread_id = std::thread::current().id();
+    eprintln!("[DEBUG] ThreadScope::new() on thread {:?} - calling ext_php_rs_sapi_per_thread_init", thread_id);
     unsafe {
       ext_php_rs_sapi_per_thread_init();
     }
+    eprintln!("[DEBUG] ThreadScope::new() on thread {:?} - ext_php_rs_sapi_per_thread_init complete", thread_id);
     Self()
   }
 }
 
 impl Drop for ThreadScope {
   fn drop(&mut self) {
+    let thread_id = std::thread::current().id();
+    eprintln!("[DEBUG] ThreadScope::drop() on thread {:?} - calling ext_php_rs_sapi_per_thread_shutdown", thread_id);
     unsafe {
       ext_php_rs_sapi_per_thread_shutdown();
     }
+    eprintln!("[DEBUG] ThreadScope::drop() on thread {:?} - ext_php_rs_sapi_per_thread_shutdown complete", thread_id);
   }
 }