Update requirements.txt with smart injection and real embeddings

requirements.txt

@@ -1,5 +1,14 @@
-faiss-cpu
-networkx
-rank_bm25
-numpy
-gradio
+# Core dependencies
+numpy>=1.21.0
+
+# Embedding & Search (optional but recommended)
+sentence-transformers>=2.2.0  # Real embeddings (fallback to hash if not installed)
+faiss-cpu>=1.7.0              # Fast similarity search
+rank_bm25>=0.2.0              # Keyword search
+networkx>=2.6.0               # Knowledge graph
+
+# Demo & MCP
+gradio>=4.0.0                 # Demo interface
+
+# Optional: for MCP server
+# fastmcp>=0.1.0