feat(character): appearance/motive 全栈穿线 + motive/traits 口径重切

打通 appearance/motive 从生成→schema→契约→落库→前端整条穿线
（DB 列早在初始迁移、此前一直 NULL，无新迁移），并原子重切人物
内驱口径。

- @llm: CharacterCard/character-gen.md 加 appearance/motive（给默认值守
  解析韧性），重切——动机唯一落 motive、traits 只留核心/表层/阴影三层、
  arc 引用 motive；regen prompt_hashes.json 金标准。
- @backend: CharacterCardView + CharacterWriteRepo/SqlCharacterWriteRepo
  （create + update backfill 分支）+ CharacterWriteFields + 路由双向形变
  与 _existing_characters 带上两字段。
- @frontend: pnpm gen:api 重生成 TS 客户端；CharacterCardItem 展示/编辑
  两字段。
- 测试: schema 默认值/解析、动机不双写重切回归、card_to_view 双向、
  ingest 透传、list 暴露、SqlCharacterWriteRepo create/backfill 真 pg 集成。

tests/test_m5_e2e.py

@@ -101,6 +101,8 @@ _CHARACTER_CARDS = CharacterGenResult(
             name="叶无尘",
             role="主角",
             traits=["隐忍", "腹黑"],
+            appearance="剑眉星目，玄袍加身，眉心一点朱砂",
+            motive="核心动机：查明灭门真相并复仇；深处渴望守护余下之人",
             backstory="灭门遗孤，背负血仇。",
             arc="从复仇者走向守护者。",
             speech_tics=["呵，有意思", "不过如此"],
@@ -393,6 +395,9 @@ async def test_m5_generate_characters_gate_acknowledge_and_persist(
             assert ye.relations == []
             assert ye.role == "主角"
             assert ye.backstory == "灭门遗孤，背负血仇。"
+            # ⑧ 穿线：appearance/motive Text 列真落 pg（此前一直 NULL）。
+            assert ye.appearance == "剑眉星目，玄袍加身，眉心一点朱砂"
+            assert ye.motive == "核心动机：查明灭门真相并复仇；深处渴望守护余下之人"
 
             # 记账真落 pg：world generate(writer) + characters generate(writer) +
             # precheck(analyst, 409 路径) + precheck(analyst, 入库路径) = 4 条。
@@ -412,6 +417,72 @@ async def test_m5_generate_characters_gate_acknowledge_and_persist(
             await _cleanup(e2e_sm, project_uuid)
 
 
+async def test_m5_character_upsert_backfills_appearance_motive(
+    e2e_sm: async_sessionmaker[AsyncSession],
+) -> None:
+    """⑧ 穿线回归：老角色（appearance/motive 为空）再次 upsert 应回填两列（update 分支）。
+
+    直连 `SqlCharacterWriteRepo`（不经端点）钉住 update 分支对新列赋值——否则老角色
+    永远补不上 appearance/motive（风险 8）。
+    """
+    from ww_api.services.credentials import STUB_OWNER_ID
+    from ww_api.services.project_deps import seed_stub_user
+    from ww_core.domain.character_repo import SqlCharacterWriteRepo
+    from ww_core.domain.project_repo import ProjectCreate, SqlProjectRepo
+
+    def _card_kwargs(appearance: str, motive: str) -> dict[str, object]:
+        return {
+            "name": "旧角色",
+            "role": "配角",
+            "traits": ["沉默"],
+            "appearance": appearance,
+            "motive": motive,
+            "backstory": "早期入库",
+            "arc": "无",
+            "speech_tics": [],
+            "tags": [],
+            "relations": [],
+        }
+
+    project_uuid: uuid.UUID | None = None
+    try:
+        # Arrange：seed stub user + 建项目 + 先入一张 appearance/motive 为空的老卡。
+        async with e2e_sm() as s:
+            await seed_stub_user(s)
+            project = await SqlProjectRepo(s).create(
+                STUB_OWNER_ID, ProjectCreate(title="⑧ 回填验证")
+            )
+            project_uuid = uuid.UUID(str(project.id))
+            await SqlCharacterWriteRepo(s).create(project_uuid, **_card_kwargs("", ""))  # type: ignore[arg-type]
+            await s.commit()
+
+        # Act：同名再次 upsert，这次带 appearance/motive（模拟重生成补全）。
+        async with e2e_sm() as s:
+            await SqlCharacterWriteRepo(s).create(
+                project_uuid,
+                **_card_kwargs("满脸风霜，独臂", "替旧主守住一个秘密"),  # type: ignore[arg-type]
+            )
+            await s.commit()
+
+        # Assert：仍一行（按 (project_id,name) upsert），两列被回填。
+        async with e2e_sm() as verify:
+            rows = (
+                (
+                    await verify.execute(
+                        select(Character).where(Character.project_id == project_uuid)
+                    )
+                )
+                .scalars()
+                .all()
+            )
+            assert len(rows) == 1
+            assert rows[0].appearance == "满脸风霜，独臂"
+            assert rows[0].motive == "替旧主守住一个秘密"
+    finally:
+        if project_uuid is not None:
+            await _cleanup(e2e_sm, project_uuid)
+
+
 async def test_m5_provider_fallback_serves_when_primary_fails(
     e2e_sm: async_sessionmaker[AsyncSession],
 ) -> None: