feat(auth): add comprehensive authentication system with 2FA support

- Add new auth module with captcha, login, logout, register, and email verification endpoints
- Implement two-factor authentication with TOTP enable, disable, verify, and backup codes regeneration
- Create RSA public key endpoint for secure password encryption
- Add user profile management with get current user and email retrieval
- Integrate OpenAPI documentation for all authentication endpoints
- Implement password reset functionality with email verification flow
- Add comprehensive API response structures with proper error handling
- Configure all auth routes under /api/v1/auth scope with proper tagging

api/auth/disable_2fa.rs

@@ -0,0 +1,38 @@
+use actix_web::{HttpResponse, web};
+
+use crate::api::response::{ApiEmptyResponse, ApiErrorResponse};
+use crate::error::AppError;
+use crate::service::AppService;
+use crate::service::auth::totp::Disable2FAParams;
+use crate::session::Session;
+
+#[utoipa::path(
+    post,
+    path = "/api/v1/auth/2fa/disable",
+    tag = "Auth / 2FA",
+    operation_id = "authDisableTwoFactor",
+    summary = "Disable two-factor authentication",
+    description = "Disable TOTP two-factor authentication for the current signed-in user. This requires verifying both the current password and a valid TOTP code or backup code. password must be encrypted with the current session RSA public key; a successfully verified backup code is consumed.",
+    request_body(
+        content = Disable2FAParams,
+        description = "TOTP/backup code and the current password encrypted with RSA.",
+        content_type = "application/json"
+    ),
+    responses(
+        (status = 200, description = "2FA has been disabled.", body = ApiEmptyResponse),
+        (status = 400, description = "2FA is not enabled, the verification code is incorrect, the password is incorrect, or RSA decryption failed.", body = ApiErrorResponse),
+        (status = 401, description = "The current session is not authenticated.", body = ApiErrorResponse),
+        (status = 500, description = "Database write failed.", body = ApiErrorResponse)
+    )
+)]
+pub async fn handle(
+    service: web::Data<AppService>,
+    session: Session,
+    params: web::Json<Disable2FAParams>,
+) -> Result<HttpResponse, AppError> {
+    service
+        .auth
+        .auth_2fa_disable(&session, params.into_inner())
+        .await?;
+    Ok(HttpResponse::Ok().json(ApiEmptyResponse::ok("two-factor authentication disabled")))
+}