Update src/streamlit_app.py

src/streamlit_app.py

@@ -97,9 +97,27 @@ st.caption("Upload a PDF or use the sample file to explore intelligent document
 # 🧭 Sidebar (Document Library + Settings + Diagnostics)
 # ==========================================================
 with st.sidebar:
+    # 🖼️ App Logo (if available)
     if os.path.exists(LOGO_PATH):
         st.image(LOGO_PATH, width=150)
 
+    # 🧠 Reasoning Mode Toggle (Persistent)
+    if "reasoning_mode" not in st.session_state:
+        st.session_state.reasoning_mode = True  # Default ON
+
+    st.session_state.reasoning_mode = st.toggle(
+        "🧠 Enable Reasoning Mode",
+        value=st.session_state.reasoning_mode,
+        help=(
+            "When ON, the assistant can use its world knowledge and reasoning ability "
+            "to generate richer, more explanatory answers.\n\n"
+            "When OFF, it sticks strictly to the document text for factual accuracy."
+        )
+    )
+
+    st.markdown("---")
+
+    # 📚 Document Library
     st.header("📚 Document Library")
     doc_choice = st.radio(
         "Choose a document:",
@@ -109,12 +127,14 @@ with st.sidebar:
 
     st.markdown("---")
 
+    # ⚙️ Settings
     st.header("⚙️ Settings")
-    reasoning_mode = st.toggle("🧠 Enable Reasoning Mode", value=True)
     chunk_size = st.slider("Chunk Size (characters)", 300, 1200, 800, step=100)
     top_k = st.slider("Top K Results (retrieved chunks)", 1, 10, 5)
 
     st.markdown("---")
+
+    # 👨‍💻 Branding
     st.caption("👨‍💻 Built by Shubham Sharma")
     st.markdown("[📂 GitHub Repo](https://github.com/shubhamsharma170793-cpu/enterprise-knowledge-assistant)")