Implement data directory configuration and ensure its existence in the main application. Update README with comprehensive features, installation instructions, and usage guidelines for the Adastra Storage Appliance.

cmd/appliance/main.go

@@ -3,9 +3,11 @@ package main
 import (
 	"context"
 	"database/sql"
+	"fmt"
 	"log"
 	"net/http"
 	"os"
+	"path/filepath"
 	"os/signal"
 	"syscall"
 	"time"
@@ -30,8 +32,26 @@ import (
 
 func main() {
 	ctx := context.Background()
+	
+	// Determine data directory (use /opt/adastra-storage/data in production, current dir in dev)
+	dataDir := os.Getenv("DATA_DIR")
+	if dataDir == "" {
+		dataDir = os.Getenv("INSTALL_DIR")
+		if dataDir != "" {
+			dataDir = filepath.Join(dataDir, "data")
+		} else {
+			dataDir = "." // Development mode
+		}
+	}
+	
+	// Ensure data directory exists
+	if err := os.MkdirAll(dataDir, 0755); err != nil {
+		log.Fatalf("failed to create data directory: %v", err)
+	}
+	
 	// Connect simple sqlite DB (file)
-	dsn := "file:appliance.db?_foreign_keys=on"
+	dbPath := filepath.Join(dataDir, "appliance.db")
+	dsn := fmt.Sprintf("file:%s?_foreign_keys=on", dbPath)
 	sqldb, err := sql.Open("sqlite", dsn)
 	if err != nil {
 		log.Fatalf("open db: %v", err)