feat: refactor and refine authentication system with decoupled user management and admin console

src/main.rs

@@ -75,6 +75,42 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let task_repo = MongoTaskRepository::new(db.clone());
     let dev_repo = MongoDeveloperRepository::new(db.clone());
 
+    // Auto-provision initial administrator if users collection is empty
+    let users_count = db.collection::<crate::auth::models::User>("users")
+        .count_documents(mongodb::bson::doc! {})
+        .await?;
+
+    if users_count == 0 {
+        use rand::{distributions::Alphanumeric, Rng};
+        let random_password: String = rand::thread_rng()
+            .sample_iter(&Alphanumeric)
+            .take(16)
+            .map(char::from)
+            .collect();
+        let password_hash = bcrypt::hash(&random_password, bcrypt::DEFAULT_COST)?;
+        
+        let admin_username = "admin";
+        let admin_user = crate::auth::models::User {
+            id: None,
+            username: admin_username.to_string(),
+            password_hash,
+            is_admin: true,
+            created_at: chrono::Utc::now(),
+        };
+        
+        db.collection::<crate::auth::models::User>("users")
+            .insert_one(admin_user)
+            .await?;
+            
+        info!("\n\n\
+               ======================================================\n\
+               CREATED INITIAL ADMINISTRATOR ACCOUNT:\n\
+               Username: {}\n\
+               Password: {}\n\
+               ======================================================\n\n", 
+               admin_username, random_password);
+    }
+
     // 5. Initialize shared AppState
     let state = AppState {
         config: config.clone(),