feat(templates): F3b 模板库 repo + 端点（GET/POST/DELETE /templates）

- TemplateRepo/SqlTemplateRepo（list/create/delete，owner stub 过滤，只 flush 端点 commit）
- schemas/templates.py（title/body min_length=1→422）+ routers/templates.py（删不存在→404）+ main 注册
- 单测：repo CRUD/owner 隔离/frozen + 端点 201/列出/204/422×2/404

packages/core/tests/test_template_repo.py

@@ -0,0 +1,104 @@
+"""F3b 模板库 repo 单测（契约 §F3）。
+
+`TemplateRepo` = 单用户提示词模板的 list/create/delete，统一按 `owner_id` 过滤
+（单用户原型 stub）。`create`/`delete` 只 `flush()` 不 `commit()`——提交交端点事务
+（与项目其它写侧 repo 一致，见 memory/gotchas）。`delete` 返回是否删到行（端点据此 404）。
+纯内存 fake，无 DB。
+"""
+
+from __future__ import annotations
+
+import uuid
+from dataclasses import dataclass, field
+
+import pytest
+from pydantic import ValidationError
+from ww_core.domain.template_repo import TemplateCreate, TemplateRepo, TemplateView
+
+OWNER = uuid.UUID(int=1)
+OTHER_OWNER = uuid.UUID(int=2)
+
+
+@dataclass
+class _FakeTemplateRepo:
+    rows: dict[uuid.UUID, TemplateView] = field(default_factory=dict)
+    owners: dict[uuid.UUID, uuid.UUID] = field(default_factory=dict)
+    flushed: int = 0
+
+    async def create(self, owner_id: uuid.UUID, data: TemplateCreate) -> TemplateView:
+        view = TemplateView(
+            id=uuid.uuid4(),
+            title=data.title,
+            body=data.body,
+            category=data.category,
+            tool_key=data.tool_key,
+        )
+        self.rows[view.id] = view
+        self.owners[view.id] = owner_id
+        self.flushed += 1
+        return view
+
+    async def list_for_owner(self, owner_id: uuid.UUID) -> list[TemplateView]:
+        return [v for tid, v in self.rows.items() if self.owners[tid] == owner_id]
+
+    async def delete(self, owner_id: uuid.UUID, template_id: uuid.UUID) -> bool:
+        if self.rows.get(template_id) is None or self.owners.get(template_id) != owner_id:
+            return False
+        del self.rows[template_id]
+        del self.owners[template_id]
+        self.flushed += 1
+        return True
+
+
+@pytest.mark.asyncio
+async def test_create_then_list_returns_view() -> None:
+    repo: TemplateRepo = _FakeTemplateRepo()
+
+    view = await repo.create(
+        OWNER, TemplateCreate(title="爽文开局", body="主角穿越...", category=None, tool_key=None)
+    )
+    listed = await repo.list_for_owner(OWNER)
+
+    assert view.title == "爽文开局"
+    assert view.body == "主角穿越..."
+    assert [v.id for v in listed] == [view.id]
+
+
+@pytest.mark.asyncio
+async def test_list_filters_by_owner() -> None:
+    repo: TemplateRepo = _FakeTemplateRepo()
+    await repo.create(OWNER, TemplateCreate(title="a", body="b"))
+
+    assert await repo.list_for_owner(OTHER_OWNER) == []
+
+
+@pytest.mark.asyncio
+async def test_delete_existing_returns_true() -> None:
+    repo: TemplateRepo = _FakeTemplateRepo()
+    view = await repo.create(OWNER, TemplateCreate(title="a", body="b"))
+
+    deleted = await repo.delete(OWNER, view.id)
+
+    assert deleted is True
+    assert await repo.list_for_owner(OWNER) == []
+
+
+@pytest.mark.asyncio
+async def test_delete_missing_returns_false() -> None:
+    repo: TemplateRepo = _FakeTemplateRepo()
+
+    assert await repo.delete(OWNER, uuid.uuid4()) is False
+
+
+@pytest.mark.asyncio
+async def test_delete_other_owner_returns_false() -> None:
+    repo: TemplateRepo = _FakeTemplateRepo()
+    view = await repo.create(OWNER, TemplateCreate(title="a", body="b"))
+
+    assert await repo.delete(OTHER_OWNER, view.id) is False
+
+
+def test_template_view_is_frozen() -> None:
+    view = TemplateView(id=uuid.uuid4(), title="a", body="b", category=None, tool_key=None)
+    with pytest.raises(ValidationError):
+        view.title = "x"