Add detail modals and improve file browser navigation

- Implement keyboard-triggered detail modals with 'i' key
- Add directory history navigation with 'b' key
- Show file/directory info in file browser, disk info for mount points
- Improve error recovery for directory navigation failures
- Optimize directory reading performance
- Remove modal instruction text for cleaner UI
- Update README with new features and keybindings

Author: Cod-e-Codes

README.md

@@ -8,9 +8,10 @@ A terminal-based system monitor built with Rust and ratatui. Provides real-time
 
 - Real-time CPU and memory monitoring with visual progress bars
 - Interactive process viewer sorted by resource usage
-- File system navigation with keyboard controls
+- File system navigation with keyboard controls and directory history
 - Network traffic visualization with sparkline graphs
-- Multi-interface network monitoring
+- Multi-interface network monitoring with overflow detection
+- Detail modals for processes, networks, system info, and files
 - Vim-style keyboard navigation
 
 ## Installation
@@ -44,6 +45,8 @@ cargo run
 - `Home/End` - Jump to first/last item in lists
 - `Enter` - Open directories in File Explorer
 - `Backspace` - Go up one directory
+- `b` - Go back in directory history
+- `i` - Show detailed information modal
 - `r` - Refresh all data
 - `?` - Show/hide help
 - `q` or `Esc` - Quit
@@ -53,9 +56,17 @@ cargo run
 1. **System Monitor** - CPU usage, memory statistics, process count, system information
 2. **System Status** - Current time/date, disk usage, network interface statistics, system load
 3. **Process Manager** - Live process list sorted by CPU usage
-4. **File Explorer** - Directory browser with folder/file icons
+4. **File Explorer** - Directory browser with folder/file icons and navigation history
 5. **Network Graph** - Real-time network traffic with interface cycling
 
+### Detail Modals
+
+Press `i` to show detailed information:
+- **Process Manager** - Process details (PID, CPU, memory, status, command)
+- **Network Graph** - Network interface details (totals, current rates)
+- **System panels** - System information (hostname, OS, kernel, hardware)
+- **File Explorer** - File/directory info or disk usage for mount points
+
 ## Technical Details
 
 - Built with ratatui for terminal UI rendering
@@ -66,6 +77,9 @@ cargo run
 - Memory and network formatting with appropriate units
 - Bounds checking and overflow protection
 - String truncation for long names
+- Error recovery for directory navigation
+- Cached data structures for performance
+- Network counter overflow detection
 
 ## Requirements