Reconnect to a restarted Wayland compositor

Windows now outlive the compositor. On connection loss YASL sends
DISPLAY_LOST instead of closing every window, retries the connection on
a loop timer, rebuilds each toplevel with its title, size, state and GL
context, and sends DISPLAY_RESTORED. CPU windows keep their pixels;
GPU renderers drop Vulkan surfaces and GL objects on loss and rebuild
them on restore.

- Free the dead connection's objects on the next wait, after the
  application has released GPU objects built on them.
- Report a lost connection as an event rather than a failed wait.
- Refuse window and Vulkan surface creation while offline with the new
  YASL_ERROR_DISCONNECTED.
- Close popups, cancel drags and fail pending clipboard requests on loss.
- Print only protocol errors, not ordinary disconnects.
- Examples survive a restart; game.c rebinds its GL context.
- Add an end-to-end test that kills Weston under CPU, GL and Vulkan
  windows and requires them to recover.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/common/vulkan.c b/src/common/vulkan.c
index 1bca415..62bc3a0 100644
--- a/src/common/vulkan.c
+++ b/src/common/vulkan.c
@@ -55,6 +55,7 @@ VkResult yasl_vulkan_create_surface(yasl_surface *s,VkInstance instance,const Vk
 {
     if(out)*out=VK_NULL_HANDLE;
     if(!yasl_public_surface(s,false)||!instance||!out||!get_proc){yasl_public_fail(EINVAL);return VK_ERROR_INITIALIZATION_FAILED;}
+    if(s->display->offline){yasl_public_fail(ENOTCONN);return VK_ERROR_SURFACE_LOST_KHR;}
     if(s->presenter!=YASL_PRIVATE_PRESENTER_NONE){yasl_public_fail(EBUSY);return VK_ERROR_NATIVE_WINDOW_IN_USE_KHR;}
     VkResult result=VK_ERROR_EXTENSION_NOT_PRESENT;
     switch(s->display->ops->type) {