chore(quality): apply ruff autofixes and formatting (223 fixes, regression-free: 118/118 tests pass)

app/schemas/note.py

@@ -3,7 +3,6 @@
 from __future__ import annotations
 
 from datetime import datetime
-from typing import Optional
 
 from pydantic import BaseModel, ConfigDict, Field
 
@@ -21,7 +20,7 @@ class NoteCreate(BaseModel):
 class NoteUpdate(BaseModel):
     """Body for PATCH /api/v1/notes/{id}."""
 
-    body: Optional[str] = Field(None, min_length=1)
+    body: str | None = Field(None, min_length=1)
 
 
 class NoteOut(BaseModel):
@@ -37,7 +36,7 @@ class NoteOut(BaseModel):
     parent_id: int
     created_at: datetime
     updated_at: datetime
-    deleted_at: Optional[datetime] = None
+    deleted_at: datetime | None = None
 
 
 __all__ = ["NoteCreate", "NoteOut", "NoteUpdate"]