[verified] add upload size and MIME guards

(cherry picked from commit f5e05376f6)

routers/database/files/files.py

@@ -12,6 +12,7 @@ from modules.auth.supabase_bearer import SupabaseBearer, verify_supabase_jwt_str
 from modules.logger_tool import initialise_logger
 from modules.database.supabase.utils.client import SupabaseServiceRoleClient
 from modules.database.supabase.utils.storage import StorageAdmin
+from modules.upload_validation import read_upload_bytes
 from modules.document_processor import DocumentProcessor
 from modules.queue_system import (
     enqueue_tika_task, enqueue_docling_task, enqueue_split_map_task,
@@ -88,13 +89,13 @@ async def upload_file(
     # Stage DB row to get file_id
     staged_path = f"{cabinet_id}/staging/{uuid.uuid4()}"
     name = _safe_filename(path or file.filename)
-    file_bytes = await file.read()
+    file_bytes, mime_type = await read_upload_bytes(file)
     insert_res = client.supabase.table('files').insert({
         'cabinet_id': cabinet_id,
         'name': name,
         'path': staged_path,
         'bucket': bucket,
-        'mime_type': file.content_type,
+        'mime_type': mime_type,
         'uploaded_by': user_id,
         'size_bytes': len(file_bytes),
         'source': 'classroomcopilot-web'
@@ -107,7 +108,7 @@ async def upload_file(
     # Final storage path: bucket/cabinet_id/file_id/file
     final_storage_path = f"{cabinet_id}/{file_id}/{name}"
     try:
-        storage.upload_file(bucket, final_storage_path, file_bytes, file.content_type or 'application/octet-stream', upsert=True)
+        storage.upload_file(bucket, final_storage_path, file_bytes, mime_type, upsert=True)
     except Exception as e:
         # cleanup staged row
         client.supabase.table('files').delete().eq('id', file_id).execute()