Initial Claude implementation

app/schemas/token.py

@@ -0,0 +1,17 @@
+from pydantic import BaseModel
+
+
+class Token(BaseModel):
+    access_token: str
+    refresh_token: str
+    token_type: str = "bearer"
+
+
+class TokenRefreshRequest(BaseModel):
+    refresh_token: str
+
+
+class LogoutRequest(BaseModel):
+    # Optional: revoke a specific refresh token. If omitted, all of the
+    # current user's refresh tokens are revoked.
+    refresh_token: str | None = None