refactor(backend): update reimbursement and expense claims

- endpoints/reimbursements.py: update reimbursement API endpoint
- schemas/reimbursement.py: update reimbursement data schemas
- services/expense_claims.py: update expense claims service logic

server/src/app/api/v1/endpoints/reimbursements.py

@@ -5,13 +5,21 @@ from typing import Annotated
 from fastapi import APIRouter, Depends, HTTPException, status
 from sqlalchemy.orm import Session
 
-from app.api.deps import get_db
+from app.api.deps import CurrentUserContext, get_current_user, get_db
 from app.schemas.common import ErrorResponse
-from app.schemas.reimbursement import ReimbursementCreate, ReimbursementRead
+from app.schemas.reimbursement import (
+    ExpenseClaimActionResponse,
+    ExpenseClaimItemUpdate,
+    ExpenseClaimRead,
+    ReimbursementCreate,
+    ReimbursementRead,
+)
+from app.services.expense_claims import ExpenseClaimService
 from app.services.reimbursement import ReimbursementService
 
 router = APIRouter()
 DbSession = Annotated[Session, Depends(get_db)]
+CurrentUser = Annotated[CurrentUserContext, Depends(get_current_user)]
 
 
 @router.get(
@@ -35,6 +43,137 @@ def create_reimbursement(payload: ReimbursementCreate, db: DbSession) -> Reimbur
     return ReimbursementService(db).create_reimbursement(payload)
 
 
+@router.get(
+    "/claims",
+    response_model=list[ExpenseClaimRead],
+    summary="查询个人报销单列表",
+    description="返回当前登录用户可见的真实个人报销单据列表。",
+)
+def list_expense_claims(db: DbSession, current_user: CurrentUser) -> list[ExpenseClaimRead]:
+    return ExpenseClaimService(db).list_claims(current_user)
+
+
+@router.get(
+    "/claims/{claim_id}",
+    response_model=ExpenseClaimRead,
+    summary="读取个人报销单详情",
+    description="根据报销单主键读取真实报销详情与费用明细。",
+    responses={
+        status.HTTP_404_NOT_FOUND: {
+            "model": ErrorResponse,
+            "description": "报销单不存在。",
+        }
+    },
+)
+def get_expense_claim(claim_id: str, db: DbSession, current_user: CurrentUser) -> ExpenseClaimRead:
+    claim = ExpenseClaimService(db).get_claim(claim_id, current_user)
+    if claim is None:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Claim not found")
+    return claim
+
+
+@router.patch(
+    "/claims/{claim_id}/items/{item_id}",
+    response_model=ExpenseClaimRead,
+    summary="更新草稿费用明细",
+    description="更新草稿报销单中的单条费用明细。",
+    responses={
+        status.HTTP_404_NOT_FOUND: {
+            "model": ErrorResponse,
+            "description": "报销单或费用明细不存在。",
+        },
+        status.HTTP_400_BAD_REQUEST: {
+            "model": ErrorResponse,
+            "description": "草稿状态校验失败或字段校验失败。",
+        },
+    },
+)
+def update_expense_claim_item(
+    claim_id: str,
+    item_id: str,
+    payload: ExpenseClaimItemUpdate,
+    db: DbSession,
+    current_user: CurrentUser,
+) -> ExpenseClaimRead:
+    service = ExpenseClaimService(db)
+    try:
+        claim = service.update_claim_item(
+            claim_id=claim_id,
+            item_id=item_id,
+            payload=payload,
+            current_user=current_user,
+        )
+    except LookupError as error:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(error)) from error
+    except ValueError as error:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(error)) from error
+
+    if claim is None:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Claim not found")
+    return claim
+
+
+@router.post(
+    "/claims/{claim_id}/submit",
+    response_model=ExpenseClaimRead,
+    summary="提交个人报销草稿",
+    description="校验草稿信息完整性后，将报销单提交到审批流程。",
+    responses={
+        status.HTTP_404_NOT_FOUND: {
+            "model": ErrorResponse,
+            "description": "报销单不存在。",
+        },
+        status.HTTP_400_BAD_REQUEST: {
+            "model": ErrorResponse,
+            "description": "草稿信息不完整或状态不允许提交。",
+        },
+    },
+)
+def submit_expense_claim(claim_id: str, db: DbSession, current_user: CurrentUser) -> ExpenseClaimRead:
+    service = ExpenseClaimService(db)
+    try:
+        claim = service.submit_claim(claim_id, current_user)
+    except ValueError as error:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(error)) from error
+
+    if claim is None:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Claim not found")
+    return claim
+
+
+@router.delete(
+    "/claims/{claim_id}",
+    response_model=ExpenseClaimActionResponse,
+    summary="删除个人报销草稿",
+    description="删除当前登录用户可见的草稿报销单。",
+    responses={
+        status.HTTP_404_NOT_FOUND: {
+            "model": ErrorResponse,
+            "description": "报销单不存在。",
+        },
+        status.HTTP_400_BAD_REQUEST: {
+            "model": ErrorResponse,
+            "description": "仅草稿状态允许删除。",
+        },
+    },
+)
+def delete_expense_claim(claim_id: str, db: DbSession, current_user: CurrentUser) -> ExpenseClaimActionResponse:
+    service = ExpenseClaimService(db)
+    try:
+        claim = service.delete_claim(claim_id, current_user)
+    except ValueError as error:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(error)) from error
+
+    if claim is None:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Claim not found")
+
+    return ExpenseClaimActionResponse(
+        message=f"{claim.claim_no} 草稿已删除。",
+        claim_id=claim.id,
+        status="deleted",
+    )
+
+
 @router.get(
     "/{request_id}",
     response_model=ReimbursementRead,