[PM-28748] Add RegistrationClient (#579)

## 🎟️ Tracking

https://bitwarden.atlassian.net/browse/PM-28748

## 📔 Objective

<!-- Describe what the purpose of this PR is, for example what bug
you're fixing or new feature you're adding. -->

Adds a stub for the registration client. This will be used by all 4
setup methods - JIT Password, JIT TDE, JIT Key-Connector and regular
master password. The cryptography code will live in a separate client.

As described in the tech breakdown, the client will call high level KM
APIs, then call HTTP requests, and return the results. It will not set
to state in the current work.
## 🚨 Breaking Changes

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2. Explain why the change was necessary
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## ⏰ Reminders before review

- Contributor guidelines followed
- All formatters and local linters executed and passed
- Written new unit and / or integration tests where applicable
- Protected functional changes with optionality (feature flags)
- Used internationalization (i18n) for all UI strings
- CI builds passed
- Communicated to DevOps any deployment requirements
- Updated any necessary documentation (Confluence, contributing docs) or
informed the documentation
  team

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  issue and could potentially benefit from discussion
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Author: quexten

crates/bitwarden-auth/src/auth_client.rs

@@ -2,7 +2,9 @@ use bitwarden_core::Client;
 #[cfg(feature = "wasm")]
 use wasm_bindgen::prelude::*;
 
-use crate::{identity::IdentityClient, send_access::SendAccessClient};
+use crate::{
+    identity::IdentityClient, registration::RegistrationClient, send_access::SendAccessClient,
+};
 
 /// Subclient containing auth functionality.
 #[derive(Clone)]
@@ -32,6 +34,11 @@ impl AuthClient {
     pub fn send_access(&self) -> SendAccessClient {
         SendAccessClient::new(self.client.clone())
     }
+
+    /// Client for initializing user account cryptography and unlock methods after JIT provisioning
+    pub fn registration(&self) -> RegistrationClient {
+        RegistrationClient::new(self.client.clone())
+    }
 }
 
 /// Extension trait for `Client` to provide access to the `AuthClient`.

crates/bitwarden-auth/src/lib.rs

@@ -3,6 +3,7 @@
 mod auth_client;
 
 pub mod identity;
+pub mod registration;
 pub mod send_access;
 
 pub(crate) mod api; // keep internal to crate

crates/bitwarden-auth/src/registration.rs

@@ -0,0 +1,36 @@
+//! Client for account registration and cryptography initialization related API methods.
+//! It is used both for the initial registration request in the case of password registrations,
+//! and for cryptography initialization for a jit provisioned user. After a method
+//! on this client is called, the user account should have initialized account keys, an
+//! authentication method such as SSO or master password, and a decryption method such as
+//! key-connector, TDE, or master password.
+
+use bitwarden_core::Client;
+#[cfg(feature = "wasm")]
+use wasm_bindgen::prelude::*;
+
+/// Client for initializing a user account.
+#[derive(Clone)]
+#[cfg_attr(feature = "wasm", wasm_bindgen)]
+pub struct RegistrationClient {
+    #[allow(dead_code)]
+    pub(crate) client: Client,
+}
+
+impl RegistrationClient {
+    pub(crate) fn new(client: Client) -> Self {
+        Self { client }
+    }
+}
+#[cfg_attr(feature = "wasm", wasm_bindgen)]
+impl RegistrationClient {
+    /// Example method to demonstrate usage of the client.
+    /// Note: This will be removed once real methods are implemented.
+    #[allow(unused)]
+    async fn example(&self) {
+        let client = &self.client.internal;
+        #[allow(unused_variables)]
+        let api_client = &client.get_api_configurations().await.api_client;
+        // Do API request here. It will be authenticated using the client's tokens.
+    }
+}