Fix PyMuPDF dependency conflict and verify RAG functionality

- Remove conflicting frontend package
- Install PyMuPDF, faiss-cpu, python-docx successfully
- Verify document processing and vector store functionality
- Add test sample file and confirm end-to-end RAG workflow

test_sample.txt

@@ -0,0 +1,8 @@
+This is a sample document for testing the RAG functionality.
+It contains multiple paragraphs of text that will be processed and chunked.
+
+The vector store will create embeddings for these chunks and allow semantic search.
+This enables context-aware responses based on uploaded documents.
+
+The system supports PDF, DOCX, TXT, and Markdown files.
+It uses FAISS for efficient similarity search and sentence transformers for embeddings.