Revert Dockerfile: base image + cookie support files + MongoDB

Update Dockerfile to copy all backend files

Deploy missing file: backend/upstream/__init__.py

Deploy missing file: backend/upstream/payload_builder.py

Deploy missing file: backend/toolcall/__init__.py

Deploy missing file: backend/toolcall/stream_state.py

Deploy missing file: backend/toolcall/parser.py

Deploy missing file: backend/toolcall/normalize.py

Deploy missing file: backend/toolcall/formats_xml.py

Deploy missing file: backend/toolcall/formats_json.py

Deploy missing file: backend/toolcall/fallback_textkv.py

Deploy missing file: backend/services/upstream_file_uploader.py

Deploy missing file: backend/services/truncation_recovery.py

Deploy missing file: backend/services/topic_isolation.py

Deploy missing file: backend/services/tool_validator.py

Deploy missing file: backend/services/tool_parser.py

Deploy missing file: backend/services/tool_name_obfuscation.py

Deploy missing file: backend/services/tool_few_shot.py

Deploy missing file: backend/services/tool_arg_fixer.py

Deploy missing file: backend/services/token_calc.py

Deploy missing file: backend/services/task_session.py

Deploy missing file: backend/services/standard_request_builder.py

Deploy missing file: backend/services/schema_compressor.py

Deploy missing file: backend/services/response_formatters.py

Deploy missing file: backend/services/refusal_cleaner.py

Deploy missing file: backend/services/prompt_builder.py

Deploy missing file: backend/services/openai_stream_translator.py

Deploy missing file: backend/services/incremental_text_streamer.py

Deploy missing file: backend/services/garbage_collector.py

Deploy missing file: backend/services/file_store.py

Deploy missing file: backend/services/file_content_cache.py

Deploy missing file: backend/services/context_offload.py

Deploy missing file: backend/services/context_cleanup.py

Deploy missing file: backend/services/context_attachment_manager.py

Deploy missing file: backend/services/completion_bridge.py

Deploy missing file: backend/services/client_profiles.py

Deploy missing file: backend/services/chat_id_pool.py

Deploy missing file: backend/services/auth_quota.py

Deploy missing file: backend/services/attachment_preprocessor.py

Deploy missing file: backend/runtime/__init__.py

Deploy missing file: backend/runtime/stream_runtime.py

Deploy missing file: backend/runtime/stream_presenter.py

Deploy missing file: backend/runtime/stream_metrics.py

Deploy missing file: backend/runtime/execution.py

Deploy missing file: backend/runtime/attachment_types.py

Deploy missing file: backend/core/account_pool/__init__.py

Deploy missing file: backend/core/account_pool/pool_core.py

Deploy missing file: backend/core/account_pool/pool_acquire.py

Deploy missing file: backend/core/__init__.py

Deploy missing file: backend/core/upstream_file_cache.py