Refactor comprehensive demos to use coro::sync_wait instead of process_events

Replaced the spawn + process_events polling pattern with cleaner sync_wait
approach across all comprehensive demos for consistency and efficiency.

Changes:
- Refactored demo_task from CORO_TASK(void) to CORO_TASK(bool)
- Removed result_flag and completed_flag pointer parameters
- Replaced scheduler->spawn() + process_events() loop with coro::sync_wait()
- Added explicit scheduler->shutdown() calls to prevent thread leaks

Benefits:
- Cleaner, more maintainable code (-60 lines, +24 lines)
- Consistent pattern across all demos
- Proper thread cleanup via shutdown()
- More idiomatic coroutine usage

Files modified:
- demos/comprehensive/src/pointers/shared_ptr_demo.cpp
- demos/comprehensive/src/pointers/optimistic_ptr_demo.cpp
- demos/comprehensive/src/transport/local_transport_demo.cpp
- demos/comprehensive/src/transport/tcp_transport_demo.cpp
- demos/comprehensive/src/serialisation/serialisation_demo.cpp

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

Author: edwardbr

demos/comprehensive/src/pointers/optimistic_ptr_demo.cpp

@@ -268,22 +268,19 @@ namespace comprehensive
             CO_RETURN true;
         }
 
-        CORO_TASK(void)
+        CORO_TASK(bool)
         demo_task(
 #ifdef CANOPY_BUILD_COROUTINE
-            std::shared_ptr<coro::io_scheduler> scheduler,
+            std::shared_ptr<coro::io_scheduler> scheduler
 #endif
-            bool* result_flag,
-            bool* completed_flag)
+        )
         {
             bool res = CO_AWAIT run_optimistic_ptr_demo(
 #ifdef CANOPY_BUILD_COROUTINE
                 scheduler
 #endif
             );
-            *result_flag = res;
-            *completed_flag = true;
-            CO_RETURN;
+            CO_RETURN res;
         }
 
     }
@@ -345,15 +342,9 @@ int main()
             .execution_strategy = coro::io_scheduler::execution_strategy_t::process_tasks_on_thread_pool
         });
 
-    bool result = false;
-    bool completed = false;
+    bool result = coro::sync_wait(comprehensive::v1::demo_task(scheduler));
 
-    scheduler->spawn(comprehensive::v1::demo_task(scheduler, &result, &completed));
-
-    while (!completed)
-    {
-        scheduler->process_events(std::chrono::milliseconds(1));
-    }
+    scheduler->shutdown();
 
     return result ? 0 : 1;
 #else

demos/comprehensive/src/pointers/shared_ptr_demo.cpp

@@ -212,22 +212,19 @@ namespace comprehensive
             CO_RETURN true;
         }
 
-        CORO_TASK(void)
+        CORO_TASK(bool)
         demo_task(
 #ifdef CANOPY_BUILD_COROUTINE
-            std::shared_ptr<coro::io_scheduler> scheduler,
+            std::shared_ptr<coro::io_scheduler> scheduler
 #endif
-            bool* result_flag,
-            bool* completed_flag)
+        )
         {
             bool res = CO_AWAIT run_shared_ptr_demo(
 #ifdef CANOPY_BUILD_COROUTINE
                 scheduler
 #endif
             );
-            *result_flag = res;
-            *completed_flag = true;
-            CO_RETURN;
+            CO_RETURN res;
         }
 
     }
@@ -279,15 +276,9 @@ int main()
             .execution_strategy = coro::io_scheduler::execution_strategy_t::process_tasks_on_thread_pool
         });
 
-    bool result = false;
-    bool completed = false;
+    bool result = coro::sync_wait(comprehensive::v1::demo_task(scheduler));
 
-    scheduler->spawn(comprehensive::v1::demo_task(scheduler, &result, &completed));
-
-    while (!completed)
-    {
-        scheduler->process_events(std::chrono::milliseconds(1));
-    }
+    scheduler->shutdown();
 
     return result ? 0 : 1;
 #else

demos/comprehensive/src/serialisation/serialisation_demo.cpp

@@ -221,22 +221,19 @@ namespace comprehensive
             CO_RETURN true;
         }
 
-        CORO_TASK(void)
+        CORO_TASK(bool)
         demo_task(
 #ifdef CANOPY_BUILD_COROUTINE
-            std::shared_ptr<coro::io_scheduler> scheduler,
+            std::shared_ptr<coro::io_scheduler> scheduler
 #endif
-            bool* result_flag,
-            bool* completed_flag)
+        )
         {
             bool res = CO_AWAIT run_serialisation_demo(
 #ifdef CANOPY_BUILD_COROUTINE
                 scheduler
 #endif
             );
-            *result_flag = res;
-            *completed_flag = true;
-            CO_RETURN;
+            CO_RETURN res;
         }
     }
 }
@@ -285,15 +282,9 @@ int main()
             .execution_strategy = coro::io_scheduler::execution_strategy_t::process_tasks_on_thread_pool
         });
 
-    bool result = false;
-    bool completed = false;
+    bool result = coro::sync_wait(comprehensive::v1::demo_task(scheduler));
 
-    scheduler->spawn(comprehensive::v1::demo_task(scheduler, &result, &completed));
-
-    while (!completed)
-    {
-        scheduler->process_events(std::chrono::milliseconds(1));
-    }
+    scheduler->shutdown();
 
     return result ? 0 : 1;
 #else

demos/comprehensive/src/transport/local_transport_demo.cpp

@@ -148,22 +148,19 @@ namespace comprehensive
             CO_RETURN true;
         }
 
-        CORO_TASK(void)
+        CORO_TASK(bool)
         demo_task(
 #ifdef CANOPY_BUILD_COROUTINE
-            std::shared_ptr<coro::io_scheduler> scheduler,
+            std::shared_ptr<coro::io_scheduler> scheduler
 #endif
-            bool* result_flag,
-            bool* completed_flag)
+        )
         {
             bool res = CO_AWAIT run_local_transport_demo(
 #ifdef CANOPY_BUILD_COROUTINE
                 scheduler
 #endif
             );
-            *result_flag = res;
-            *completed_flag = true;
-            CO_RETURN;
+            CO_RETURN res;
         }
     }
 }
@@ -214,15 +211,9 @@ int main()
             .execution_strategy = coro::io_scheduler::execution_strategy_t::process_tasks_on_thread_pool
         });
 
-    bool result = false;
-    bool completed = false;
+    bool result = coro::sync_wait(comprehensive::v1::demo_task(scheduler));
 
-    scheduler->spawn(comprehensive::v1::demo_task(scheduler, &result, &completed));
-
-    while (!completed)
-    {
-        scheduler->process_events(std::chrono::milliseconds(1));
-    }
+    scheduler->shutdown();
 
     return result ? 0 : 1;
 #else

demos/comprehensive/src/transport/tcp_transport_demo.cpp

@@ -277,14 +277,15 @@ int main()
     return 1;
 #else
 
-    auto scheduler = coro::io_scheduler::make_shared(
-        coro::io_scheduler::options{
-            .thread_strategy = coro::io_scheduler::thread_strategy_t::spawn,
-            .pool = coro::thread_pool::options{
-                .thread_count = std::thread::hardware_concurrency(),
-            },
-            .execution_strategy = coro::io_scheduler::execution_strategy_t::process_tasks_on_thread_pool
-        });
+    auto scheduler_1 = coro::io_scheduler::make_shared(
+        coro::io_scheduler::options{.thread_strategy = coro::io_scheduler::thread_strategy_t::spawn,
+            .pool = coro::thread_pool::options{.thread_count = 4},
+            .execution_strategy = coro::io_scheduler::execution_strategy_t::process_tasks_on_thread_pool});
+
+    auto scheduler_2 = coro::io_scheduler::make_shared(
+        coro::io_scheduler::options{.thread_strategy = coro::io_scheduler::thread_strategy_t::spawn,
+            .pool = coro::thread_pool::options{.thread_count = 4},
+            .execution_strategy = coro::io_scheduler::execution_strategy_t::process_tasks_on_thread_pool});
 
     for (int i = 0; i < 100; i++)
     {
@@ -295,11 +296,13 @@ int main()
         // this tells that the client has finished so the server can shutdown
         rpc::event client_finished;
 
-        coro::sync_wait(coro::when_all(comprehensive::v1::run_tcp_server(scheduler, server_ready, client_finished),
-            comprehensive::v1::run_tcp_client(scheduler, server_ready, client_finished)));
+        coro::sync_wait(coro::when_all(comprehensive::v1::run_tcp_server(scheduler_1, server_ready, client_finished),
+            comprehensive::v1::run_tcp_client(scheduler_2, server_ready, client_finished)));
     }
 
     print_separator("TCP TRANSPORT DEMO COMPLETED");
+    scheduler_1->shutdown();
+    scheduler_2->shutdown();
     return 0;
 #endif
 }