feat(IdentityClientStub): [PM-23835] Stub out auth identity client (#546)

## 🎟️ Tracking
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point to where this change is coming from. -->
https://bitwarden.atlassian.net/browse/PM-23835

## 📔 Objective
<!-- Describe what the purpose of this PR is, for example what bug
you're fixing or new feature you're adding. -->
To stub out the auth client > identity client 

## ⏰ 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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Author: JaredSnider-Bitwarden

crates/bitwarden-auth/src/auth_client.rs

@@ -2,7 +2,7 @@ use bitwarden_core::Client;
 #[cfg(feature = "wasm")]
 use wasm_bindgen::prelude::*;
 
-use crate::send_access::SendAccessClient;
+use crate::{identity::IdentityClient, send_access::SendAccessClient};
 
 /// Subclient containing auth functionality.
 #[derive(Clone)]
@@ -23,6 +23,11 @@ impl AuthClient {
 
 #[cfg_attr(feature = "wasm", wasm_bindgen)]
 impl AuthClient {
+    /// Client for identity functionality
+    pub fn identity(&self) -> IdentityClient {
+        IdentityClient::new(self.client.clone())
+    }
+
     /// Client for send access functionality
     pub fn send_access(&self) -> SendAccessClient {
         SendAccessClient::new(self.client.clone())

crates/bitwarden-auth/src/identity/client.rs

@@ -0,0 +1,38 @@
+use bitwarden_core::Client;
+#[cfg(feature = "wasm")]
+use wasm_bindgen::prelude::*;
+
+/// The IdentityClient is used to obtain identity / access tokens from the Bitwarden Identity API.
+#[derive(Clone)]
+#[cfg_attr(feature = "wasm", wasm_bindgen)]
+pub struct IdentityClient {
+    #[allow(dead_code)] // TODO: Remove when methods using client are implemented
+    pub(crate) client: Client,
+}
+
+impl IdentityClient {
+    /// Create a new IdentityClient with the given Client.
+    pub(crate) fn new(client: Client) -> Self {
+        Self { client }
+    }
+}
+
+#[cfg_attr(feature = "wasm", wasm_bindgen)]
+impl IdentityClient {
+    // TODO: Add methods to interact with the Identity API.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_identity_client_creation() {
+        let client: Client = Client::new(None);
+        let identity_client = IdentityClient::new(client);
+
+        // Verify the identity client was created successfully
+        // The client field is present and accessible
+        let _ = identity_client.client;
+    }
+}

crates/bitwarden-auth/src/identity/mod.rs

@@ -0,0 +1,5 @@
+//! Identity client module
+//! The IdentityClient is used to obtain identity / access tokens from the Bitwarden Identity API.
+mod client;
+
+pub use client::IdentityClient;

crates/bitwarden-auth/src/lib.rs

@@ -2,6 +2,7 @@
 
 mod auth_client;
 
+pub mod identity;
 pub mod send_access;
 
 pub(crate) mod api; // keep internal to crate