chore: import upstream snapshot with attribution

docs/api_reference/theme/mlflow/header.html

@@ -0,0 +1,50 @@
+<div class="header-container">
+  <style scoped>
+    .header-container {
+      display: flex;
+      flex-direction: row;
+      align-items: center;
+      justify-content: space-between;
+      padding: 8px 16px;
+
+      background-color: #fff;
+      box-shadow: 0 1px 2px 0 #0000001a;
+    }
+
+    .logo-container {
+      display: flex;
+      gap: 12px;
+      flex-direction: row;
+      white-space: nowrap;
+      align-items: center;
+      justify-content: center;
+    }
+
+    a:hover {
+      text-decoration: none;
+      color: #0194e2;
+    }
+  </style>
+  <div class="logo-container">
+    <i
+      data-toggle="wy-nav-top"
+      class="wy-nav-top-menu-button db-icon db-icon-menu pull-left"
+    ></i>
+    <a href="{{ pathto(master_doc) }}" class="wy-nav-top-logo">
+      <img
+        src="{{ pathto('_static/MLflow-logo-final-black.png', 1) }}"
+        alt="MLflow"
+      />
+    </a>
+    <a
+      style="overflow: hidden; text-overflow: ellipsis"
+      class="header-link"
+      href="/docs/latest"
+      >Main Docs</a
+    >
+    <span style="overflow: hidden; text-overflow: ellipsis" class="header-link"
+      >API Documentation</span
+    >
+  </div>
+  <span class="header-link version">{{version}}</span>
+</div>