feat(video-render): worker.py — Redis BLPOP + 4 job_type dispatch (SP-7)

queue:video-render BLPOP, queue:paused 체크 후 dispatch.
string-based _DISPATCH_TABLE + getattr (테스트 patch 호환, Plan-B-Music 패턴).
AttributeError 가드 포함. asyncio.to_thread로 sync provider wrap.
4 job_type: sora/veo/kling/seedance _generation.
Plan-B-Video Phase 2.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

services/video-render/tests/test_worker.py

@@ -0,0 +1,43 @@
+"""worker.py — job_type 디스패처 (4 provider)."""
+import pytest
+from unittest.mock import patch
+
+import worker
+
+
+def test_dispatch_sora_calls_run_sora_generation():
+    payload = {"task_id": "t1", "job_type": "sora_generation", "params": {"prompt": "x"}}
+    with patch("worker.run_sora_generation") as m:
+        worker._dispatch(payload)
+        m.assert_called_once_with("t1", {"prompt": "x"})
+
+
+def test_dispatch_veo_calls_run_veo_generation():
+    payload = {"task_id": "t2", "job_type": "veo_generation", "params": {"prompt": "x"}}
+    with patch("worker.run_veo_generation") as m:
+        worker._dispatch(payload)
+        m.assert_called_once_with("t2", {"prompt": "x"})
+
+
+def test_dispatch_kling_calls_run_kling_generation():
+    payload = {"task_id": "t3", "job_type": "kling_generation", "params": {"prompt": "x"}}
+    with patch("worker.run_kling_generation") as m:
+        worker._dispatch(payload)
+        m.assert_called_once_with("t3", {"prompt": "x"})
+
+
+def test_dispatch_seedance_calls_run_seedance_generation():
+    payload = {"task_id": "t4", "job_type": "seedance_generation", "params": {"prompt": "x"}}
+    with patch("worker.run_seedance_generation") as m:
+        worker._dispatch(payload)
+        m.assert_called_once_with("t4", {"prompt": "x"})
+
+
+def test_dispatch_unknown_job_type_logs_error():
+    payload = {"task_id": "t5", "job_type": "weird_type", "params": {}}
+    with patch("worker.webhook_update_task") as m:
+        worker._dispatch(payload)
+        m.assert_called_once()
+        args = m.call_args[0]
+        assert args[0] == "t5"
+        assert args[1] == "failed"