feat: 实现 executor 流式执行路径及完善 gateway 多格式 plan 构建

- Rust executor 新增流式 plan 支持，覆盖 openai/claude/gemini 的 chat/cli/video 格式
- Gateway 新增 finalize-sync、report-stream 端点及 stream report 模型
- 新增 video sync 操作(create/cancel/remix/delete)的 plan 构建
- 修正 OpenAI Responses(openai:cli) SSE 格式: 添加 event: 行、移除 [DONE] 哨兵
- 统一 OpenAI CLI normalizer 的 ID 生成方法

tests/api/handlers/base/test_cli_sse_helpers.py

@@ -0,0 +1,32 @@
+import json
+
+from src.api.handlers.base.cli_sse_helpers import _format_converted_events_to_sse
+
+
+def test_format_converted_events_to_sse_uses_event_lines_for_openai_cli() -> None:
+    events = [
+        {
+            "type": "response.output_text.delta",
+            "item_id": "msg_123",
+            "output_index": 0,
+            "content_index": 0,
+            "delta": "Hi",
+            "logprobs": [],
+            "sequence_number": 1,
+        }
+    ]
+
+    lines = _format_converted_events_to_sse(events, "openai:cli")
+
+    assert lines == [
+        "event: response.output_text.delta\n"
+        f"data: {json.dumps(events[0], ensure_ascii=False)}\n"
+    ]
+
+
+def test_format_converted_events_to_sse_keeps_data_only_for_openai_chat() -> None:
+    events = [{"id": "chatcmpl-123", "object": "chat.completion.chunk", "choices": []}]
+
+    lines = _format_converted_events_to_sse(events, "openai:chat")
+
+    assert lines == [f"data: {json.dumps(events[0], ensure_ascii=False)}\n"]