fix(ui): add accessibility attrs and click-outside handling to dropdown components

CortexDropdownMenu: add role="menu" to container div, add onClickOutside
optional prop with document mousedown listener registered in onMount and
cleaned up in onCleanup, using a ref on the container div.

CortexDropdownItem: add role="menuitem" and tabindex="0" to the button
element for proper keyboard accessibility and ARIA semantics.

CortexGitPanel: move document.addEventListener("mousedown", ...) into an
onMount() block to follow SolidJS lifecycle best practices (was previously
called at component top-level which is a SolidJS antipattern).

Author: echobt

src/components/cortex/CortexGitPanel.tsx

@@ -138,7 +138,9 @@ export const CortexGitPanel: Component = () => {
   const handleClickOutside = (e: MouseEvent) => {
     if (showDotsMenu() && dotsRef && !dotsRef.contains(e.target as Node)) setShowDotsMenu(false);
   };
-  document.addEventListener("mousedown", handleClickOutside);
+  onMount(() => {
+    document.addEventListener("mousedown", handleClickOutside);
+  });
   onCleanup(() => document.removeEventListener("mousedown", handleClickOutside));
 
   onMount(() => { if (repo()) fetchStashes(); });

src/components/cortex/primitives/CortexDropdownItem.tsx

@@ -106,6 +106,8 @@ export const CortexDropdownItem: Component<CortexDropdownItemProps> = (props) =>
   return (
     <button
       type="button"
+      role="menuitem"
+      tabindex="0"
       class={local.class}
       style={baseStyle()}
       onClick={handleClick}

src/components/cortex/primitives/CortexDropdownMenu.tsx

@@ -3,13 +3,14 @@
  * Figma "Dropdown Menu": standalone container with dark bg and border
  */
 
-import { Component, JSX, splitProps } from "solid-js";
+import { Component, JSX, splitProps, onMount, onCleanup } from "solid-js";
 
 export interface CortexDropdownMenuProps {
   children?: JSX.Element;
   width?: number;
   class?: string;
   style?: JSX.CSSProperties;
+  onClickOutside?: () => void;
 }
 
 export const CortexDropdownMenu: Component<CortexDropdownMenuProps> = (props) => {
@@ -18,8 +19,21 @@ export const CortexDropdownMenu: Component<CortexDropdownMenuProps> = (props) =>
     "width",
     "class",
     "style",
+    "onClickOutside",
   ]);
 
+  let menuRef: HTMLDivElement | undefined;
+
+  onMount(() => {
+    const handleMouseDown = (e: MouseEvent) => {
+      if (menuRef && !menuRef.contains(e.target as Node)) {
+        local.onClickOutside?.();
+      }
+    };
+    document.addEventListener("mousedown", handleMouseDown);
+    onCleanup(() => document.removeEventListener("mousedown", handleMouseDown));
+  });
+
   const menuWidth = () => local.width ?? 243;
 
   const containerStyle = (): JSX.CSSProperties => ({
@@ -38,6 +52,8 @@ export const CortexDropdownMenu: Component<CortexDropdownMenuProps> = (props) =>
 
   return (
     <div
+      ref={menuRef}
+      role="menu"
       class={local.class}
       style={containerStyle()}
       {...others}