feat(faq): refine category icons and project faq flows

backend/app/crud/faq_category.py

@@ -14,7 +14,7 @@ async def create_category(db: AsyncSession, category_in: CategoryCreate) -> FaqC
         name=category_in.name,
         description=category_in.description,
         sort_order=category_in.sort_order,
-        is_active=category_in.is_active,
+        icon=category_in.icon,
     )
     db.add(category)
     await db.commit()
@@ -26,15 +26,12 @@ async def list_categories(
     db: AsyncSession,
     study_id: uuid.UUID | None,
     include_global: bool = True,
-    is_active: bool | None = True,
 ) -> Sequence[FaqCategory]:
     stmt = select(FaqCategory)
     if include_global:
         stmt = stmt.where((FaqCategory.study_id == study_id) | (FaqCategory.study_id.is_(None)))
     else:
         stmt = stmt.where(FaqCategory.study_id == study_id)
-    if is_active is not None:
-        stmt = stmt.where(FaqCategory.is_active == is_active)
     stmt = stmt.order_by(FaqCategory.sort_order, FaqCategory.name)
     result = await db.execute(stmt)
     return result.scalars().all()
@@ -59,6 +56,22 @@ async def get_category_by_name(
     return result.scalar_one_or_none()
 
 
+async def get_category_by_icon(
+    db: AsyncSession,
+    study_id: uuid.UUID | None,
+    icon: str,
+) -> FaqCategory | None:
+    if not icon:
+        return None
+    stmt = select(FaqCategory).where(FaqCategory.icon == icon)
+    if study_id is None:
+        stmt = stmt.where(FaqCategory.study_id.is_(None))
+    else:
+        stmt = stmt.where(FaqCategory.study_id == study_id)
+    result = await db.execute(stmt)
+    return result.scalar_one_or_none()
+
+
 async def update_category(db: AsyncSession, category: FaqCategory, category_in: CategoryUpdate) -> FaqCategory:
     update_data = category_in.model_dump(exclude_unset=True)
     if update_data: