Three bugs fixed:
1. Close and iconify buttons broken after frame rendering model change
Buttons are composited into the titlebar buffer, so their scene_buf
nodes carry no committed buffer and are invisible to wlr_scene_node_at.
frame_buf_at() returned the titlebar fb for all button-area clicks,
routing them to titlebarMouseDown instead of buttonMouseDown.
Fix: add frame_buf_button_at() -- coordinate walk of frame_list entries
with scene_buf->buffer == NULL -- and frame_buf_hit() which tries button
resolution first then falls back to the scene graph. Replace all
frame_buf_at() calls in button and motion handlers with frame_buf_hit().
Also emit synthetic WME_LEAVE/WME_ENTER events on sub-window boundary
crossings so buttonMouseDown's press-track loop works correctly.
2. Iconify crash (SIGSEGV in update_icon_title)
WMDrawString() was passed icon->core->window (a frame_buf synthetic ID,
0x10000000+) as the drawable. wl_font_resolve_drawable() only recognised
WINGs view IDs (0x20000000+), so it cast the frame_buf ID directly as a
pixman_image_t* -- wild pointer -- SIGSEGV.
Fix: add W_RegisterBacking()/W_UnregisterBacking() to wview_wl.c.
Register each frame_buf's pixman image in the backing table on creation
and unregister on destroy. Extend the ID range check in wfont_wl.c and
wrender_wl.c from 0x20000000 down to 0x10000000 so frame_buf IDs resolve
correctly via W_GetViewBacking().
3. Resizebar visible after iconify + miniwindow not rendering
wl_window_unmap() disabled fb->scene_buf->node individually, but a
subsequent wl_frame_paint() could re-enable and re-commit it while the
window was still iconified.
Fix: for top-level frames, disable fb->tree->node -- hides the entire
scene tree (frame buffer, titlebar, resizebar, client surface) atomically.
Symmetric enable in wl_window_map().
Miniwindow icons were invisible: icon_paint was a noop so the frame_buf
image was never committed to the scene graph. Add wl_icon_paint() mirroring
wl_appicon_paint(): tile + file_image composite + title text, committed
via wlr_scene_buffer_set_buffer(). Wire into wIconPaint() in icon.c so
the backend finalises the surface after policy-layer setup.
d29f2a29c9