feat(auth): implement user registration and login with JWT authentication

- Added `bcrypt`, `jsonwebtoken`, and `once_cell` dependencies to manage password hashing and JWT handling.
- Created `Claims` struct for JWT claims and implemented token generation in the login route.
- Implemented user registration and authentication logic in the `auth` module.
- Updated error handling to include validation errors.
- Created new routes for user registration and login, and integrated them into the main router.
- Added tests for the authentication flow, including registration and login scenarios.
- Updated user model to include a password hash field.
- Refactored user creation logic to include password validation.
- Adjusted feed and user routes to utilize JWT for authentication.

thoughts-backend/migration/src/m20240101_000001_init.rs

@@ -24,6 +24,8 @@ impl MigrationTrait for Migration {
                             .not_null()
                             .unique_key(),
                     )
+                    .to_owned()
+                    .col(ColumnDef::new(User::PasswordHash).string())
                     .to_owned(),
             )
             .await
@@ -41,4 +43,5 @@ pub(super) enum User {
     Table,
     Id,
     Username,
+    PasswordHash,
 }