Add comprehensive offline help system with fuzzy search

🎯 Enhanced Features:
- Integrated navi, cheat, tldr, and fzf for interactive help
- Custom cheat sheets for PDF analysis, malware analysis, and system utilities
- find-tool command for fuzzy searching through all REMnux tools
- Comprehensive help command with workflows and examples
- Complete offline documentation system

📚 Help System Components:
- help                    - Main help system
- help tools [term]       - Search for tools (fuzzy matching)
- help cheat <tool>       - Show command examples
- help examples           - Browse examples interactively (navi + fzf)
- help pdf/malware/forensics - Analysis workflows
- help --offline          - Verify offline capabilities

🛠️ Tools Added:
- navi: Interactive cheat sheet browser
- cheat: Command-line cheat sheets
- tldr: Quick command examples
- fzf: Fuzzy finder (already included)

All documentation works completely offline with local REMnux docs database
and custom cheat sheets for analysis workflows.

cheatsheets/system-utilities.cheat

@@ -0,0 +1,121 @@
+# System Utilities and Forensics
+# Essential commands for file analysis and system operations
+
+% system, forensics, utilities
+
+# Archive operations with 7zip
+7z l <archive_file>
+
+# Extract archive
+7z x <archive_file>
+
+# Create archive
+7z a <output_archive> <files_to_compress>
+
+# Extract with password
+7z x -p<password> <archive_file>
+
+# File manager with Midnight Commander
+mc
+
+# Navigate MC with panels
+mc <left_dir> <right_dir>
+
+# Convert document formats
+catdoc <doc_file>
+
+# Extract text from DOCX
+docx2txt <docx_file>
+
+# Convert RTF to text
+unrtf --text <rtf_file>
+
+# Advanced text processing with busybox
+busybox <command> <args>
+
+# Find files by type
+find /data -name "*.<extension>" -type f
+
+# Find files modified in last N days
+find /data -mtime -<days> -type f
+
+# Search for text in files
+grep -r "<search_term>" /data/
+
+# Case-insensitive search
+grep -ri "<search_term>" /data/
+
+# Search with context lines
+grep -C <context_lines> "<search_term>" <file>
+
+# Count file types in directory
+find /data -name "*.*" | sed 's/.*\.//' | sort | uniq -c | sort -n
+
+# Quick file statistics
+wc -l <file>
+
+# Get file size in human readable format
+du -sh <file_or_directory>
+
+# Monitor file changes
+tail -f <log_file>
+
+# Compare files
+diff <file1> <file2>
+
+# Create file hash (multiple algorithms)
+md5sum <file>
+sha1sum <file>
+sha256sum <file>
+
+# Verify file integrity
+md5sum -c <checksum_file>
+
+# Network utilities (if needed for analysis)
+curl -I <url>
+
+# Download file safely
+wget --no-check-certificate <url>
+
+# Show disk usage
+df -h
+
+# Show memory usage
+free -h
+
+# Process monitoring
+ps aux | grep <process_name>
+
+# Environment variables
+printenv | sort
+
+# File permissions
+ls -la <file>
+
+# Change permissions
+chmod <permissions> <file>
+
+$ archive_file: ls *.zip *.7z *.tar.gz *.rar
+$ output_archive: echo "output.7z"
+$ files_to_compress: echo "file1.txt file2.txt"
+$ password: echo "password123"
+$ left_dir: echo "/data"
+$ right_dir: echo "/tmp"
+$ doc_file: ls *.doc
+$ docx_file: ls *.docx
+$ rtf_file: ls *.rtf
+$ command: echo "ls cat grep find"
+$ args: echo "-la"
+$ extension: echo "pdf txt log exe"
+$ days: echo "1 7 30"
+$ search_term: echo "malware suspicious error"
+$ context_lines: echo "3 5 10"
+$ file: ls *
+$ file_or_directory: echo "/data"
+$ log_file: ls *.log
+$ file1: echo "file1.txt"
+$ file2: echo "file2.txt"
+$ checksum_file: echo "checksums.md5"
+$ url: echo "https://example.com"
+$ process_name: echo "python nginx apache"
+$ permissions: echo "755 644 600"