Add Dangerous Pi MVP implementation - complete backend and system integration

This commit adds the complete Dangerous Pi web management interface with all MVP features implemented and tested locally.

## New Features

### Backend (Python + FastAPI)
- Complete FastAPI backend with async support
- 40+ API endpoints (Health, PM3, WiFi, Updates, UPS, BLE, Plugins)
- 6 managers: Session, WiFi, Update, UPS, BLE, Plugin
- SQLite database with sessions, config, history, crash reports
- Server-Sent Events (SSE) for real-time notifications
- Mock PM3 worker for development without hardware

### WiFi Manager
- Interface detection (USB vs built-in)
- Network scanning with signal strength
- Mode switching (AP/Client/Dual/Auto/Off)
- Network connection with password support
- Hidden SSID and saved networks support
- Static IP and DHCP configuration
- 10 WiFi API endpoints

### Update Manager
- GitHub releases API integration
- Automatic periodic update checks
- Semantic version comparison
- Update download with progress tracking
- SHA256 checksum verification
- Automatic installation with backup and rollback
- PM3 client rebuild after updates
- 6 Update API endpoints

### UPS Manager
- I2C battery monitoring (MAX17040-compatible)
- Battery percentage, voltage, current tracking
- Power source detection (AC/Battery)
- Safe shutdown triggers at configurable thresholds
- Event callbacks for battery warnings
- SSE and BLE notification integration
- 3 UPS API endpoints

### BLE Manager
- Bluetooth Low Energy notification support
- Auto-detects BLE capability
- Multiple notification types (updates, battery, shutdown, etc.)
- BLE advertising management
- Device connection tracking
- 4 BLE API endpoints

### Plugin Framework
- Dynamic plugin loading/unloading
- Plugin lifecycle management (load, enable, disable, unload)
- Hook system for extensibility
- JSON-based metadata
- Example "Hello World" plugin included
- 7 Plugin API endpoints

### Frontend (Remix.js + React)
- Cyberpunk-themed responsive UI
- Dashboard with system status
- PM3 command interface with history
- Settings page with WiFi and Update management
- Command logs viewer
- Theme toggle (Dark/Light/Auto)
- Server-side rendering (SSR)
- Mobile-first responsive design

### System Integration
- Systemd service with security hardening
- Automated install/uninstall scripts
- Environment configuration template
- Hardware access groups (i2c, bluetooth, gpio, dialout)
- Pi-gen stage 04 integration for OS image building
- Port conflict resolution with ttyd-bash
- I2C interface auto-enable for UPS HAT

### Testing
- test_backend.py - Backend API tests
- test_ups.py - UPS manager tests
- test_ble.py - BLE manager tests
- test_plugins.py - Plugin manager tests
- All tests passing locally

### Documentation
- 12 comprehensive documentation files
- claude.md - AI development guide
- WIFI_MANAGER.md - WiFi management guide
- UPDATE_MANAGER.md - Update system guide
- PORT_CONFLICT.md - Port conflict resolution guide
- MVP_COMPLETE.md - MVP implementation summary
- PROJECT_STATUS.md - Project status and roadmap
- systemd/README.md - Service management docs
- pi-gen integration documentation

## Technical Details
- ~5,000+ lines of backend code
- 11 Python dependencies (smbus2 added for UPS)
- FastAPI with async/await throughout
- Type hints and docstrings on all functions
- RESTful API design with SSE for notifications
- Security hardening (non-root, protected dirs, resource limits)

## Next Steps
- Deploy to Raspberry Pi Zero 2 W hardware
- Test with real Proxmark3 device
- Test UPS HAT integration
- Test BLE on Pi hardware
- Build custom OS image with pi-gen
- Performance optimization for Pi Zero 2 W

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

systemd/README.md

@@ -0,0 +1,235 @@
+# Dangerous Pi Systemd Service
+
+This directory contains systemd service files and installation scripts for running Dangerous Pi as a system service.
+
+## Files
+
+- `dangerous-pi.service` - Main systemd service unit file
+- `dangerous-pi.env.example` - Environment configuration template
+- `install-service.sh` - Installation script
+- `uninstall-service.sh` - Uninstallation script
+
+## Installation
+
+### Automated Installation
+
+Run the installation script as root:
+
+```bash
+cd /path/to/dangerous-pi/systemd
+sudo ./install-service.sh
+```
+
+This will:
+1. Copy the service file to `/etc/systemd/system/`
+2. Create the environment configuration file at `/opt/dangerous-pi/.env`
+3. Create data and logs directories
+4. Add the `pi` user to required hardware access groups
+5. Enable the service to start on boot
+
+### Manual Installation
+
+If you prefer to install manually:
+
+```bash
+# Copy service file
+sudo cp dangerous-pi.service /etc/systemd/system/
+
+# Copy environment template
+sudo cp dangerous-pi.env.example /opt/dangerous-pi/.env
+
+# Create directories
+sudo mkdir -p /opt/dangerous-pi/data /opt/dangerous-pi/logs
+sudo chown -R pi:pi /opt/dangerous-pi/data /opt/dangerous-pi/logs
+
+# Add pi user to groups
+sudo usermod -a -G i2c,bluetooth,gpio,dialout pi
+
+# Reload systemd and enable service
+sudo systemctl daemon-reload
+sudo systemctl enable dangerous-pi
+```
+
+## Configuration
+
+Edit the environment file to customize your installation:
+
+```bash
+sudo nano /opt/dangerous-pi/.env
+```
+
+Available configuration options:
+- `PM3_DEVICE` - Proxmark3 device path (default: `/dev/ttyACM0`)
+- `PM3_TIMEOUT` - PM3 command timeout in seconds
+- `SESSION_TIMEOUT` - User session timeout in seconds
+- `HOST` - Server bind address (default: `0.0.0.0`)
+- `PORT` - Server port (default: `8000`)
+- `GITHUB_REPO` - GitHub repository for updates
+- `UPS_I2C_ADDRESS` - I2C address for UPS HAT
+- `BLE_ENABLED` - Enable/disable BLE notifications
+- `AUTH_ENABLED` - Enable/disable authentication
+- See `dangerous-pi.env.example` for all options
+
+## Service Management
+
+### Start the service
+
+```bash
+sudo systemctl start dangerous-pi
+```
+
+### Stop the service
+
+```bash
+sudo systemctl stop dangerous-pi
+```
+
+### Restart the service
+
+```bash
+sudo systemctl restart dangerous-pi
+```
+
+### Check service status
+
+```bash
+sudo systemctl status dangerous-pi
+```
+
+### View service logs
+
+```bash
+# View recent logs
+sudo journalctl -u dangerous-pi
+
+# Follow logs in real-time
+sudo journalctl -u dangerous-pi -f
+
+# View logs since boot
+sudo journalctl -u dangerous-pi -b
+```
+
+### Enable service (start on boot)
+
+```bash
+sudo systemctl enable dangerous-pi
+```
+
+### Disable service (don't start on boot)
+
+```bash
+sudo systemctl disable dangerous-pi
+```
+
+## Uninstallation
+
+Run the uninstallation script as root:
+
+```bash
+cd /path/to/dangerous-pi/systemd
+sudo ./uninstall-service.sh
+```
+
+This will:
+1. Stop the service if running
+2. Disable the service
+3. Remove the service unit file
+4. Reload systemd daemon
+
+Note: Application files in `/opt/dangerous-pi` are NOT removed automatically.
+
+## Security Features
+
+The service includes security hardening:
+- Runs as non-root user (`pi`)
+- Private `/tmp` directory
+- Protected system directories
+- Read-only application directory (except for `data` and `logs`)
+- Resource limits (memory, CPU, file descriptors)
+- No new privileges allowed
+
+## Hardware Access
+
+The service is configured to access the following hardware:
+- I2C devices (for UPS HAT) via `i2c` group
+- Bluetooth (for BLE notifications) via `bluetooth` group
+- GPIO pins via `gpio` group
+- Serial devices (for Proxmark3) via `dialout` group
+
+## Troubleshooting
+
+### Service fails to start
+
+Check the logs for errors:
+```bash
+sudo journalctl -u dangerous-pi -n 50
+```
+
+### Permission denied errors
+
+Ensure the `pi` user is in the required groups:
+```bash
+groups pi
+```
+
+Should include: `i2c`, `bluetooth`, `gpio`, `dialout`
+
+### Port already in use
+
+The default port (8000) conflicts with ttyd-bash from pi-pm3. See the main README for resolution options.
+
+### Can't access Proxmark3
+
+Ensure the PM3 device path is correct in `/opt/dangerous-pi/.env`:
+```bash
+PM3_DEVICE=/dev/ttyACM0
+```
+
+Check that the device exists:
+```bash
+ls -l /dev/ttyACM*
+```
+
+## Advanced Configuration
+
+### Custom Installation Directory
+
+To use a different installation directory, edit the service file before installation:
+
+```bash
+WorkingDirectory=/your/custom/path
+ReadWritePaths=/your/custom/path/data /your/custom/path/logs
+```
+
+### Different User/Group
+
+To run as a different user, edit the service file:
+
+```bash
+User=your-user
+Group=your-group
+```
+
+Don't forget to add the user to required hardware groups.
+
+### Resource Limits
+
+Adjust resource limits in the service file:
+
+```bash
+MemoryMax=1G           # Maximum memory
+CPUQuota=100%          # CPU usage limit
+LimitNOFILE=131072     # Max open files
+```
+
+## Integration with pi-pm3
+
+When running alongside the existing pi-pm3 setup:
+
+1. **Port Conflict**: Port 8000 is used by ttyd-bash. Options:
+   - Change Dangerous Pi port in `.env`: `PORT=8001`
+   - Disable ttyd-bash: `sudo systemctl disable ttyd-bash`
+
+2. **RaspAP Compatibility**: Dangerous Pi WiFi manager can coexist with RaspAP or replace it.
+
+3. **PM3 Access**: Only one service should access PM3 at a time. Disable ttyd-pm3 if using Dangerous Pi's PM3 interface.

systemd/dangerous-pi.env.example

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+# Dangerous Pi Environment Configuration
+# Copy this file to /opt/dangerous-pi/.env and customize as needed
+
+# PM3 Configuration
+PM3_DEVICE=/dev/ttyACM0
+PM3_TIMEOUT=30
+
+# Session Configuration
+SESSION_TIMEOUT=300
+
+# Server Configuration
+HOST=0.0.0.0
+PORT=8000
+VERSION=1.0.0
+
+# Update Configuration
+GITHUB_REPO=yourusername/dangerous-pi
+UPDATE_CHECK_INTERVAL=3600
+
+# Wi-Fi Configuration
+WLAN_INTERFACE=wlan0
+USB_WLAN_INTERFACE=wlan1
+
+# UPS Configuration
+UPS_I2C_ADDRESS=0x36
+UPS_CHECK_INTERVAL=60
+
+# BLE Configuration
+BLE_ENABLED=true
+BLE_DEVICE_NAME=DangerousPi
+
+# Security
+AUTH_ENABLED=false
+HTTPS_ENABLED=false

systemd/dangerous-pi.service

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+[Unit]
+Description=Dangerous Pi Backend Service
+Documentation=https://github.com/yourusername/dangerous-pi
+After=network.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=pi
+Group=pi
+WorkingDirectory=/opt/dangerous-pi
+Environment="PATH=/usr/local/bin:/usr/bin:/bin"
+Environment="PYTHONUNBUFFERED=1"
+EnvironmentFile=-/opt/dangerous-pi/.env
+
+# Main service command
+ExecStart=/usr/bin/python3 -m uvicorn app.backend.main:app \
+    --host 0.0.0.0 \
+    --port 8000 \
+    --log-level info
+
+# Restart policy
+Restart=always
+RestartSec=10
+StartLimitBurst=5
+StartLimitInterval=60
+
+# Resource limits
+LimitNOFILE=65536
+MemoryMax=512M
+CPUQuota=80%
+
+# Security hardening
+NoNewPrivileges=true
+PrivateTmp=true
+ProtectSystem=strict
+ProtectHome=true
+ReadWritePaths=/opt/dangerous-pi/data /opt/dangerous-pi/logs
+ReadOnlyPaths=/opt/dangerous-pi
+
+# Allow I2C and Bluetooth access
+SupplementaryGroups=i2c bluetooth gpio dialout
+
+# Graceful shutdown
+TimeoutStopSec=30
+KillMode=mixed
+KillSignal=SIGTERM
+
+[Install]
+WantedBy=multi-user.target

systemd/install-service.sh

@@ -0,0 +1,67 @@
+#!/bin/bash
+# Installation script for Dangerous Pi systemd service
+
+set -e
+
+echo "Installing Dangerous Pi systemd service..."
+
+# Check if running as root
+if [ "$EUID" -ne 0 ]; then
+    echo "Error: This script must be run as root (use sudo)"
+    exit 1
+fi
+
+# Variables
+SERVICE_NAME="dangerous-pi"
+SERVICE_FILE="dangerous-pi.service"
+INSTALL_DIR="/opt/dangerous-pi"
+SYSTEMD_DIR="/etc/systemd/system"
+
+# Create installation directory if it doesn't exist
+if [ ! -d "$INSTALL_DIR" ]; then
+    echo "Creating installation directory: $INSTALL_DIR"
+    mkdir -p "$INSTALL_DIR"
+fi
+
+# Copy service file to systemd directory
+echo "Installing systemd service unit..."
+cp "$(dirname "$0")/$SERVICE_FILE" "$SYSTEMD_DIR/"
+chmod 644 "$SYSTEMD_DIR/$SERVICE_FILE"
+
+# Create .env file if it doesn't exist
+if [ ! -f "$INSTALL_DIR/.env" ]; then
+    echo "Creating environment configuration file..."
+    cp "$(dirname "$0")/dangerous-pi.env.example" "$INSTALL_DIR/.env"
+    chown pi:pi "$INSTALL_DIR/.env"
+    chmod 600 "$INSTALL_DIR/.env"
+    echo "NOTE: Please edit $INSTALL_DIR/.env to configure your installation"
+fi
+
+# Create data and logs directories
+echo "Creating data and logs directories..."
+mkdir -p "$INSTALL_DIR/data"
+mkdir -p "$INSTALL_DIR/logs"
+chown -R pi:pi "$INSTALL_DIR/data" "$INSTALL_DIR/logs"
+chmod 755 "$INSTALL_DIR/data" "$INSTALL_DIR/logs"
+
+# Add pi user to required groups for hardware access
+echo "Adding pi user to hardware access groups..."
+usermod -a -G i2c,bluetooth,gpio,dialout pi || true
+
+# Reload systemd daemon
+echo "Reloading systemd daemon..."
+systemctl daemon-reload
+
+# Enable service to start on boot
+echo "Enabling $SERVICE_NAME service..."
+systemctl enable "$SERVICE_NAME.service"
+
+echo ""
+echo "✅ Installation complete!"
+echo ""
+echo "Next steps:"
+echo "  1. Edit configuration: sudo nano $INSTALL_DIR/.env"
+echo "  2. Start the service: sudo systemctl start $SERVICE_NAME"
+echo "  3. Check status: sudo systemctl status $SERVICE_NAME"
+echo "  4. View logs: sudo journalctl -u $SERVICE_NAME -f"
+echo ""

systemd/uninstall-service.sh

@@ -0,0 +1,47 @@
+#!/bin/bash
+# Uninstallation script for Dangerous Pi systemd service
+
+set -e
+
+echo "Uninstalling Dangerous Pi systemd service..."
+
+# Check if running as root
+if [ "$EUID" -ne 0 ]; then
+    echo "Error: This script must be run as root (use sudo)"
+    exit 1
+fi
+
+# Variables
+SERVICE_NAME="dangerous-pi"
+SERVICE_FILE="dangerous-pi.service"
+SYSTEMD_DIR="/etc/systemd/system"
+
+# Stop the service if running
+if systemctl is-active --quiet "$SERVICE_NAME"; then
+    echo "Stopping $SERVICE_NAME service..."
+    systemctl stop "$SERVICE_NAME"
+fi
+
+# Disable the service
+if systemctl is-enabled --quiet "$SERVICE_NAME" 2>/dev/null; then
+    echo "Disabling $SERVICE_NAME service..."
+    systemctl disable "$SERVICE_NAME"
+fi
+
+# Remove service file
+if [ -f "$SYSTEMD_DIR/$SERVICE_FILE" ]; then
+    echo "Removing service unit file..."
+    rm "$SYSTEMD_DIR/$SERVICE_FILE"
+fi
+
+# Reload systemd daemon
+echo "Reloading systemd daemon..."
+systemctl daemon-reload
+systemctl reset-failed || true
+
+echo ""
+echo "✅ Uninstallation complete!"
+echo ""
+echo "Note: Application files in /opt/dangerous-pi were NOT removed."
+echo "To remove them manually: sudo rm -rf /opt/dangerous-pi"
+echo ""