add hub instance info (#869)

- Improvement: Hub module listing now includes per-instance process metrics (memory, CPU time, working set, pagefile usage)
- Improvement: Hub now monitors provisioned instance health in the background and refreshes process metrics periodically
- Improvement: Hub no longer exposes raw `StorageServerInstance` pointers to callers; instance state is returned as value snapshots (`Hub::InstanceInfo`)
- Improvement: Hub instance access is now guarded by RAII per-instance locks (`SharedLockedPtr`/`ExclusiveLockedPtr`), preventing concurrent modifications during provisioning and deprovisioning
- Improvement: Hub instance lifecycle is now tracked as a `HubInstanceState` enum covering transitional states (Provisioning, Deprovisioning, Hibernating, Waking); exposed as a string in the HTTP API and dashboard

1 files changed, 12 insertions, 0 deletions

diff --git a/src/zencore/thread.cpp b/src/zencore/thread.cpp
index 54459cbaa..f74791333 100644
--- a/src/zencore/thread.cpp
+++ b/src/zencore/thread.cpp
@@ -146,6 +146,12 @@ RwLock::AcquireShared() noexcept
 	m_Mutex.lock_shared();
 }
 
+bool
+RwLock::TryAcquireShared() noexcept
+{
+	return m_Mutex.try_lock_shared();
+}
+
 void
 RwLock::ReleaseShared() noexcept
 {
@@ -158,6 +164,12 @@ RwLock::AcquireExclusive() noexcept
 	m_Mutex.lock();
 }
 
+bool
+RwLock::TryAcquireExclusive() noexcept
+{
+	return m_Mutex.try_lock();
+}
+
 void
 RwLock::ReleaseExclusive() noexcept
 {