feat(security): JWT required on every API route, gated dev fallback, role checks

- main.py: global get_current_user dependency on all routers except
  /auth/login and /health; prod fail-fast startup guard rejects wildcard
  CORS, default credentials, DEV_LOGIN_ENABLED
- inventory/pm: X-User-Role header identity fallback now only active when
  PROCUREMENT_DEV_LOGIN_ENABLED=true (was unconditional in production)
- item_decisions writes + attachment deletes: require_role(
  procurement_manager, admin) — require_role was defined but never used
- config.py: ENVIRONMENT flag, comma-separated CORS_ORIGINS, no default
  Casdoor client secret/admin password, DEV_LOGIN_ENABLED=false
- frontend: authenticated file downloads (Bearer + blob) — <a href> links
  cannot send the token; FileList/QuoteDetail/AcceptModal/EditModal/
  PurchaseHistory converted; DEV_LOGIN_ENABLED build arg defaults false
- smoke tests authenticate via POST /auth/login (SMOKE_USER/SMOKE_PASSWORD)
- traefik: security headers, API rate limit, 12MB body cap (prod overlay)
- nginx client_max_body_size aligned to 12MB

backend/app/routers/item_decisions.py

@@ -4,11 +4,16 @@ State machine (P1 cross-endpoint rules):
     pending -> chosen (requires chosen_item_termsheet_id of the SAME line item)
     pending -> rejected
     chosen/rejected -> pending/anything-else = 409
+
+Auth: JWT required globally (main.py). The state-changing endpoints are a
+purchase decision — restricted to procurement_manager / admin via
+require_role; reads stay open to every authenticated role.
 """
 from fastapi import APIRouter, Depends
 from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
+from app.auth import require_role
 from app.db.engine import get_db
 from app.models.procurement import ItemDecision, ItemTermsheet, LineItem
 from app.schemas.procurement import DecisionPatch, DecisionPut, DecisionStatusUpdate
@@ -21,6 +26,9 @@ router = APIRouter(
     tags=["item-decisions"],
 )
 
+# خرید/رد اقلام = تصمیم تدارکات؛ ادمین و مدیر تدارکات
+_decision_writer = require_role("procurement_manager", "admin")
+
 
 async def _line_item_or_404(db: AsyncSession, quote_id, line_item_id) -> LineItem:
     li = await db.scalar(
@@ -59,7 +67,7 @@ async def get_decision(quote_id, line_item_id, db: AsyncSession = Depends(get_db
     return {"data": decision_full(decision)}
 
 
-@router.put("")
+@router.put("", dependencies=[Depends(_decision_writer)])
 async def put_decision(
     quote_id, line_item_id, payload: DecisionPut, db: AsyncSession = Depends(get_db)
 ):
@@ -93,7 +101,7 @@ async def put_decision(
     return {"data": decision_full(decision), "status_code_hint": 201 if created else 200}
 
 
-@router.patch("/status")
+@router.patch("/status", dependencies=[Depends(_decision_writer)])
 async def patch_decision_status(
     quote_id, line_item_id, payload: DecisionStatusUpdate, db: AsyncSession = Depends(get_db)
 ):
@@ -118,7 +126,7 @@ async def patch_decision_status(
     return {"data": decision_full(decision)}
 
 
-@router.patch("")
+@router.patch("", dependencies=[Depends(_decision_writer)])
 async def patch_decision(
     quote_id, line_item_id, payload: DecisionPatch, db: AsyncSession = Depends(get_db)
 ):