feat: 后端 CRUD 完成（episodes + yearly_targets + users 管理 API）

backend/app/schemas/episode.py

@@ -0,0 +1,41 @@
+"""
+节目期次 Schema — 请求 / 响应模型
+"""
+
+from datetime import date
+
+from pydantic import BaseModel, ConfigDict
+
+from app.models.user import UserRole
+
+
+class EpisodeBase(BaseModel):
+    episode_number: int
+    program_name: str
+    air_date: date
+    editor_id: int | None = None
+    editor_name_snapshot: str
+    audience_share: float | None = None
+    audience_rating: float | None = None
+    is_rerun: bool = False
+    original_episode_id: int | None = None
+    is_time_sensitive: bool = False
+    is_outdoor_shoot: bool = False
+    outdoor_contact_person: str | None = None
+    outdoor_contact_info: str | None = None
+    lead_source: str | None = None
+    notes: str | None = None
+
+
+class EpisodeCreate(EpisodeBase):
+    pass
+
+
+class EpisodeUpdate(EpisodeBase):
+    pass
+
+
+class EpisodeResponse(EpisodeBase):
+    id: int
+
+    model_config = ConfigDict(from_attributes=True)