fix: no GPU allocation path maps, however small the buffer

The previous commit converted the allocations that scale with the
drawing and deliberately left the small fixed-size ones -- uniforms, the
viewcube's static geometry, per-image and per-wipeout quads -- reasoning
that an allocation failure was not a realistic outcome for a few dozen
bytes.

That reasoning was wrong, and the log says so precisely. On the
reproducer the vertex buffers degraded exactly as intended:

  [gpu] uncaptured ... Out of Memory
  [gpu] uncaptured ... In Queue::write_buffer
          Buffer with 'block_wire.vertices' label is invalid
  ... errors #4 #8 #16 #32 #64 #128, session kept alive

and then the process died here:

  thread 'main' panicked at wgpu_core.rs:2253:
  Error in Buffer::get_mapped_range: Validation Error
  Caused by: Buffer with 'block_wire.const' label is invalid

'block_wire.const' is a single uniform struct. Once the device is out of
memory every allocation fails, including a 32-byte one, and
create_buffer_init maps it and panics. Size was never the relevant
property -- whether the path maps is.

So every remaining allocation goes through gpu_upload too: block-wire
const, the viewcube's seven buffers, the blit and clip-boundary buffers,
image instances/params/vertices, mesh material params and surface and the
empty index stub, the texture-hatch uniform, and all five wipeout
buffers. `grep -r create_buffer_init src` now finds only a comment, and
no mapped_at_creation:true remains outside gpu_upload's own docs.

`queue` is threaded through the last holdouts: upload_wipeouts,
upload_clip_boundary, MeshBatchStubs::new and
create_material_bind_group_from_resources.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/scene/pipeline/hatch_gpu/texture.rs

@@ -3,7 +3,6 @@
 
 use crate::scene::model::hatch_model::{HatchModel, HatchPattern};
 use iced::wgpu;
-use iced::wgpu::util::DeviceExt;
 
 /// Width (in texels) of the RGBA32F data texture. Height grows to fit; a hatch
 /// with N total texels uses ceil(N / WIDTH) rows.
@@ -377,11 +376,13 @@ impl TextureHatch {
             dash_off,
             tex_width: width,
         };
-        let _uniform_buf = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
-            label: Some("hatch.texture.uniform"),
-            contents: bytemuck::bytes_of(&uniform_data),
-            usage: wgpu::BufferUsages::UNIFORM,
-        });
+        let _uniform_buf = crate::scene::pipeline::gpu_upload::upload_buffer(
+            device,
+            queue,
+            "hatch.texture.uniform",
+            std::slice::from_ref(&uniform_data),
+            wgpu::BufferUsages::UNIFORM,
+        );
 
         let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
             label: Some("hatch.texture.bind_group1"),