Merge remote-tracking branch 'origin/rustify' into worktree-agent-a27094a7db775552a

# Conflicts:
#	docs/IRIS.md

docs/IRIS_TODO.md

@@ -7,6 +7,29 @@ order and what "done" looks like. Tick and date them in place.
 
 ## Fix
 
+- [x] **`request_device` asked for compute-shader limits it never uses
+  (2026-09-05).** `Limits::default()` (both `iris/src/android/render.rs`
+  and `iris/src/default/render.rs`) requests desktop-tier compute limits
+  unconditionally, even though nothing in `iris`/`iris-core` creates a
+  `ComputePipeline` or writes a `@compute` shader stage — confirmed by
+  grepping the whole tree, not assumed. That crashed device creation
+  outright on the Android emulator's software GL path (`EMU_GPU=software`,
+  `--features force-gles`): SwiftShader's GL reports itself as OpenGL ES
+  3.0, which has no compute shaders, so the adapter's real limit is 0
+  against the unconditional request for 65535 — the same would happen on
+  any real GLES-3.0-only Android device. Fixed by a new, shared
+  `iris_core::device_limits()` (`iris/core/src/render/mod.rs`) that zeros
+  exactly the six `max_compute_*` fields rather than switching to a
+  downlevel `Limits` preset — `downlevel_webgl2_defaults()` also zeros
+  `max_storage_buffers_per_shader_stage`, which `shader.wgsl`'s vertex
+  stage needs (four `var<storage>` buffers), so that preset would trade
+  this crash for a bind-group-layout one on the same hardware.
+  `rigs/gpu-probe`'s own hand-mirrored `Limits` (it is deliberately its
+  own crate, not able to call `device_limits()` directly) was updated to
+  match. See `DECISIONS.md` and RUST.md's I5 box for the account,
+  including what could not be re-verified on-device this pass (the
+  emulator was in concurrent use by another session).
+
 - [x] **Input does not fall through by input type (2026-09-04).**
   `SensorUi::run_sensors` (`src/default/sense.rs`) used to set "consumed,
   stop checking lower layers" from mere hover — a widget registered for