feat: User management + JWT auth routes

- Admin users CRUD: /api/admin/users + /api/admin/users/{id}
- Public auth: /api/auth/register, /api/auth/login, /api/auth/me
- User model + password hashing via existing auth module
- JWT token generation and validation
- cargo check ✅ | cargo test 18/18 ✅

boosapi-rs/src/db/models/mod.rs

@@ -6,3 +6,4 @@ pub mod route_channel;
 pub mod setting;
 pub mod site;
 pub mod token_route;
+pub mod user;

boosapi-rs/src/db/models/user.rs

@@ -0,0 +1,16 @@
+use serde::{Deserialize, Serialize};
+use sqlx::FromRow;
+
+/// A platform user (admin or regular).
+#[derive(Debug, Clone, Serialize, Deserialize, FromRow)]
+pub struct User {
+    pub id: i64,
+    pub username: String,
+    pub email: String,
+    #[serde(skip_serializing)]
+    pub password_hash: String,
+    pub role: String,
+    pub status: String,
+    pub created_at: Option<String>,
+    pub updated_at: Option<String>,
+}