### `WIV1` and `WIR1` through the integer operator set's stage operators

- **`ops` members with no graph.** `wai.video.int_motion` and
  `wai.{image,video,audio,splat}.int_refine` decode through the stage operators of
  [integer-operators](extensions/integer-operators.md) §13.5 alone, and register
  `{ wai-ops/1, stage: rans64 t4097/lenient/canonical }`: with no parameter set, the
  member has no profile, subset or lowering (§11; the registry schema now requires
  `set`, those three together, and a lowering or a stage).
- **The stage operators the drivers need.** `wai-ops`' E1 decodes a symbol against a
  table in whatever width a payload's parser keeps it (`Rans::symbol_in`, and
  `table_ok` reads its entries likewise), and E10, E11 and E12 gain per-element forms
  (`mc_predict_at`, `up2_at`, `rate_at`) that read a frame, a picture or source samples
  in the driver's layout, so a decode forms no copy.
- **The switch.** `int_video::{decode_typed, decode_pframes_typed}` decode `WIV1`
  through E1, E10 and E9 (`int_video::ops`), and `staged::wir1::apply_unit` and
  `Wir1::check_streams` decode `WIR1` through E1, E11 or E12, and E9
  (`staged::wir1::ops`). Every committed output is unchanged: the `int_video` clips
  (the half-pel real footage among them) and their SHA-256 sidecars, the payload
  corpus, every stage of the staged corpus and the byte-equality goldens. The direct
  decodes are `int_video::legacy` and `staged::wir1::legacy`, test-only (`legacy_int`).
  No input decodes or refuses differently ([integer-operators](extensions/integer-operators.md)
  §15.3 item 5).
- **The 32-bit form, behind a feature.** `wai-ops`' E9 32-bit form
  (`stage::residual_step_i32`, `i32_form_fits`, and `residual_step_by_i32` for `i64`
  operands) is behind the new `i32_forms` feature, the arithmetic a 32-bit fabric runs;
  `wai-rs`' `i32_forms` decodes `WIV1` and `WIR1` through it
  (`int_video::ops::decode_typed_i32`, `staged::wir1::ops::apply_unit_i32`), held to the
  exact decode by the parity tests, the differential and the byte-equality goldens.
- **Text.** [integer-operators](extensions/integer-operators.md) §5E writes E10, E11 and
  E12 out, §13.5 the `WIV1` and `WIR1` drivers, and the status note names the stage-only
  capabilities; integer-payloads §3 and §12 and staged-delivery A.4 cite the stage
  operators; SPEC §8 lists no planned break for them.

