Apply Qwen vision RoPE per row across table boundaries

docs/issue108-vision-boundary/README.md

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+# Issue 108: row-wise attention positions
+
+Qwen attention now implements pinned MTPLX's `_vision_chunk_cos_sin` route:
+covered rows use the original table slice and M-RoPE graph; uncovered rows use
+plain RoPE at `index + delta`; mixed chunks concatenate those two tables. The
+YaRN amplitude applies to both portions. With the shipped scaling of one, wholly
+inside/outside calls build the same numerical graphs as before. The text-only
+branch and indexer remain unchanged. Production changes are confined to two
+private Qwen modules, with no DS4/GLM callers or shared numerical changes.
+
+This fixes a **latent module mismatch**. Review of `vision::prepare`, owner setup,
+model dispatch, suffix prefill and MTP history found no new product trigger:
+`prepare` builds a table over the complete rendered prompt; prefill stops within
+it, and decoding starts after it. The final post-image text positions are equal
+across axes at `index + delta`. A normal MTP window crossing that text boundary
+is therefore not a reproduction. No state rebase, prompt mutation or stale-table
+restore was added. No new DS4Server feature is involved.
+
+## Verification
+
+`tools/issue108-reference.py` runs the pinned MTPLX revision
+`9882703f3105363ddc37eca9f97aa09a1d387112` in isolated MLX 0.32.2. It uses the
+oracle's actual frequency constructor and chunk helper, plus independent NumPy
+per-row checks. Its 56 cases cover small and shipped head geometry (dim256,
+24 query heads, rotary64), F32/BF16, scaling 1/1.25, wholly inside/outside,
+unequal image-axis straddling, equal axes, absent/empty tables, and a full-prompt
+post-image text tail. Native cosine/sine and Q/K outputs match every oracle byte.
+The text-tail and equal-axis crossings also match plain shifted RoPE exactly.
+
+The owned `vision_positions` case in `issue103_vision_position_receipts` now
+requires corrected cached keys. Actual Attention calls compare one mixed chunk
+with the same input split at the table end: outputs, valid K/V, offsets and the
+next call's output/state agree exactly. The unrelated sparse-QSA and attention
+Gate diagnostic cases retain their current separate ownership (#107/#109).
+
+Existing whole-attention fixtures exercise the unchanged text/vision controls,
+cache hashes and execution routes in both TF32 modes, with lazy and prepared
+inputs. The mandatory Rust formatting, Clippy, bundle and complete ordinary test
+gates are recorded in `checks.json`; the adjacent JSONL receipts retain the
+owned test results. These are correctness checks, not performance claims.
+
+## Reproduction
+
+```sh
+local-eval-results/mtplx-reference-env-0.32.2/bin/python \
+  tools/issue108-reference.py /path/to/pinned/mtplx /tmp/issue108-oracle
+cargo test --all-features --bin ds4-server --no-run
+cargo build --bin test-supervisor
+export DS4_ISSUE108_ORACLE=/tmp/issue108-oracle
+# Use the test executable printed by cargo, not cargo itself in the supervisor.
+target/debug/test-supervisor 4096 60 120 --command TEST_EXECUTABLE \
+  issue108_attention_chunk_positions --ignored --nocapture --test-threads=1
+target/debug/test-supervisor 4096 60 120 --command TEST_EXECUTABLE \
+  issue103_vision_position_receipts --ignored --nocapture --test-threads=1
+# Run mtplx_qsa_attention_module_matches_reference the same way with
+# MLX_ENABLE_TF32=1 and then MLX_ENABLE_TF32=0, serially.
+```