scaffold: Backend core — Cargo.toml, main.rs, config, models, panel adapter

Axum server entry point, AppConfig, AppState, ApiError, all model
structs (auth, license, server, wipe), and the PanelAdapter trait
that abstracts AMP/Pterodactyl/companion connections.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/src/models/auth.rs

@@ -0,0 +1,74 @@
+use chrono::{DateTime, Utc};
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
+
+/// User record from the database
+#[derive(Debug, Clone, sqlx::FromRow, Serialize)]
+pub struct User {
+    pub id: Uuid,
+    pub email: String,
+    pub username: String,
+    #[serde(skip_serializing)]
+    pub password_hash: String,
+    #[serde(skip_serializing)]
+    pub totp_secret: Option<String>,
+    pub totp_enabled: bool,
+    #[serde(skip_serializing)]
+    pub backup_codes: Option<Vec<String>>,
+    pub email_verified: bool,
+    pub created_at: DateTime<Utc>,
+    pub last_login_at: Option<DateTime<Utc>>,
+}
+
+/// JWT claims
+#[derive(Debug, Serialize, Deserialize)]
+pub struct Claims {
+    pub sub: Uuid,          // user_id
+    pub email: String,
+    pub license_id: Option<Uuid>,
+    pub role: Option<String>,
+    pub exp: i64,
+    pub iat: i64,
+    pub token_type: String, // "access" or "refresh"
+}
+
+/// Login request
+#[derive(Debug, Deserialize)]
+pub struct LoginRequest {
+    pub email: String,
+    pub password: String,
+}
+
+/// Login response
+#[derive(Debug, Serialize)]
+pub struct AuthResponse {
+    pub access_token: String,
+    pub refresh_token: String,
+    pub requires_totp: bool,
+    pub user: UserPublic,
+}
+
+/// Public user info (no sensitive fields)
+#[derive(Debug, Serialize)]
+pub struct UserPublic {
+    pub id: Uuid,
+    pub email: String,
+    pub username: String,
+    pub totp_enabled: bool,
+    pub email_verified: bool,
+}
+
+/// Registration request
+#[derive(Debug, Deserialize)]
+pub struct RegisterRequest {
+    pub email: String,
+    pub username: String,
+    pub password: String,
+    pub license_key: String,
+}
+
+/// TOTP verification request
+#[derive(Debug, Deserialize)]
+pub struct TotpRequest {
+    pub code: String,
+}