Add automatic dependency installer and package checks

DEPENDENCY MANAGEMENT:
- Created scripts/install-dependencies.sh - automatic installer for all required packages
- Detects OS (Ubuntu, Debian, CentOS, RHEL, Fedora, Arch, macOS)
- Installs PostgreSQL client (psql) automatically
- Installs Docker & Docker Compose if missing
- Installs utility packages (curl, wget, git)

SCRIPT ENHANCEMENTS:
- Updated setup-database.sh with dependency checking
- Updated generate_data.sh with dependency checking
- Updated verify-setup.sh with dependency checking
- All scripts now prompt to run installer if dependencies are missing
- Interactive prompts guide users through installation

DOCUMENTATION:
- Updated README.md with dependency installation instructions
- Updated QUICKSTART.md with Step 0: Install Dependencies
- Added supported OS list
- Added automatic dependency check notes

USER EXPERIENCE:
- No more manual package installation required
- Scripts fail gracefully with helpful error messages
- One-command installation: ./scripts/install-dependencies.sh
- Automatic detection and installation on Linux/macOS
- Clear instructions for Windows users

This ensures users can get started immediately without hunting for package installation commands.

scripts/verify-setup.sh

@@ -22,11 +22,43 @@ DB_NAME="${POSTGRES_DB:-business_analytics}"
 DB_USER="${POSTGRES_USER:-data_analyst}"
 DB_PASSWORD="${POSTGRES_PASSWORD:-SecurePass123!}"
 
+# Script directory
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
 echo -e "${BLUE}============================================================================${NC}"
 echo -e "${BLUE}Business Analytics Database - Verification${NC}"
 echo -e "${BLUE}============================================================================${NC}"
 echo ""
 
+# Check for required dependencies
+check_dependencies() {
+    local missing_deps=()
+
+    # Check for psql
+    if ! command -v psql >/dev/null 2>&1; then
+        missing_deps+=("psql (PostgreSQL client)")
+    fi
+
+    # Check for docker
+    if ! command -v docker >/dev/null 2>&1; then
+        missing_deps+=("docker")
+    fi
+
+    if [ ${#missing_deps[@]} -gt 0 ]; then
+        echo -e "${RED}✗ Missing required dependencies:${NC}"
+        for dep in "${missing_deps[@]}"; do
+            echo -e "  - ${YELLOW}$dep${NC}"
+        done
+        echo ""
+        echo -e "${YELLOW}Run the dependency installer:${NC}"
+        echo -e "  ${GREEN}./scripts/install-dependencies.sh${NC}"
+        exit 1
+    fi
+}
+
+# Run dependency check
+check_dependencies
+
 # Function to execute SQL and get result
 execute_sql() {
     PGPASSWORD=$DB_PASSWORD psql -h $DB_HOST -p $DB_PORT -U $DB_USER -d $DB_NAME -t -c "$1" 2>/dev/null | xargs