feat(video): DashScope video specialist with correct i2v request bodies

- Add video_generation_client: async video-synthesis, t2v vs i2v (Wan 2.7 input.media first_frame vs legacy img_url).

- Coerce *-t2v* to *-i2v* when first frame present; AIA_VIDEO_I2V_INPUT_STYLE / I2V_MODEL overrides.

- Gateway/direct_loop early return for video specialist; workspace video + factory allowlist.

- Normalize WS and admin chat attachments (image_ref parity); mp4 attachment store roundtrip tests.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_file_attachments.py

@@ -575,3 +575,16 @@ def test_excel_sheet_count_cap_applies_in_tool_mode(tmp_path: Path, monkeypatch)
     notes = [x for x in out if isinstance(x, dict) and str(x.get("name") or "").endswith(".sheet-limit")]
     assert notes
 
+
+def test_attachment_asset_store_mp4_load_bytes_roundtrip(tmp_path: Path) -> None:
+    """Regression: ``load_bytes`` must resolve ``.mp4`` on-disk blobs (not only image extensions)."""
+    from oclaw.platform.files.attachment_assets import AttachmentAssetStore
+
+    ast = AttachmentAssetStore(str(tmp_path))
+    payload = b"\x00\x00\x00\x18ftypmp42\x00\x00\x00\x00mp42isom" + b"vid" * 400
+    meta = ast.save_bytes(payload, filename="clip.mp4", mime="video/mp4")
+    blob, meta2 = ast.load_bytes(meta.attachment_id)
+    assert blob == payload
+    assert meta2 is not None
+    assert meta2.bytes == len(payload)
+