refactor: simplify logging messages and remove unused code

- In chat service, reduced verbosity in log messages by removing server/prompt_name and filename details to streamline output.
- Removed unused response variable assignment in websocket endpoint.
- Eliminated unused Filter icon import from frontend component.

Author: garland3

backend/application/chat/service.py

@@ -219,9 +219,7 @@ async def handle_chat_message(
                                 # Prepend as system message override
                                 messages = [{"role": "system", "content": prompt_text}] + messages
                                 logger.info(
-                                    "Applied MCP system prompt override from %s:%s (len=%d)",
-                                    server,
-                                    prompt_name,
+                                    "Applied MCP system prompt override (len=%d)",
                                     len(prompt_text),
                                 )
                                 break  # apply only one
@@ -378,7 +376,7 @@ async def handle_attach_file(
                 update_callback=update_callback
             )
 
-            logger.info(f"Attached file {filename} ({s3_key}) to session {session_id}")
+            logger.info(f"Attached file ({s3_key}) to session {session_id}")
 
             return {
                 "type": "file_attach",

backend/main.py

@@ -226,7 +226,7 @@ async def websocket_endpoint(websocket: WebSocket):
             if message_type == "chat":
                 # Handle chat message with streaming updates
                 try:
-                    response = await chat_service.handle_chat_message(
+                    await chat_service.handle_chat_message(
                         session_id=session_id,
                         content=data.get("content", ""),
                         model=data.get("model", ""),

frontend/src/components/AllFilesView.jsx

@@ -11,7 +11,6 @@ import {
   Search,
   SortAsc,
   SortDesc,
-  Filter,
   Loader
 } from 'lucide-react'
 import { useChat } from '../contexts/ChatContext'