Implement hashed password transfer, change password, redesign the settings UI

frontend/src/core/api/securityApi.ts

@@ -0,0 +1,25 @@
+import { API_BASE_URL } from "@/core/config";
+import { getAuthHeaders, deriveAuthSecret } from "@/core/api/authApi";
+
+export async function changePassword(
+    token: string,
+    username: string,
+    currentPassword: string,
+    newPassword: string,
+    logoutAllExceptCurrent: boolean
+): Promise<void> {
+    const currentDerived = await deriveAuthSecret(username, currentPassword);
+    const newDerived = await deriveAuthSecret(username, newPassword);
+    const res = await fetch(`${API_BASE_URL}/change-password`, {
+        method: "POST",
+        headers: getAuthHeaders(token),
+        body: JSON.stringify({
+            currentPasswordDerived: currentDerived,
+            newPasswordDerived: newDerived,
+            logoutAllExceptCurrent
+        })
+    });
+    if (!res.ok) throw new Error("Failed to change password");
+}
+
+