fix(renderer): kitty images should all be processed

When processing kitty images in a loop in a few places we were returning
under certain conditions where we should instead have just continued the
loop. This caused serious problems for kitty images, especially for apps
that used multiple images on screen at once.

... I have no clue how I originally wrote this code and didn't see such
a trivial mistake, I think I was sleep deprived or something.

src/renderer/generic.zig

@@ -1551,15 +1551,17 @@ pub fn Renderer(comptime GraphicsAPI: type) type {
                 // Look up the image
                 const image = self.images.get(p.image_id) orelse {
                     log.warn("image not found for placement image_id={}", .{p.image_id});
-                    return;
+                    continue;
                 };
 
                 // Get the texture
                 const texture = switch (image.image) {
-                    .ready => |t| t,
+                    .ready,
+                    .unload_ready,
+                    => |t| t,
                     else => {
                         log.warn("image not ready for placement image_id={}", .{p.image_id});
-                        return;
+                        continue;
                     },
                 };
 
@@ -1909,7 +1911,7 @@ pub fn Renderer(comptime GraphicsAPI: type) type {
                 if (img.isUnloading()) {
                     img.deinit(self.alloc);
                     self.images.removeByPtr(kv.key_ptr);
-                    return;
+                    continue;
                 }
                 if (img.isPending()) try img.upload(self.alloc, &self.api);
             }