Cloud feedback Extension (#6626)

This pull request introduces a new extensible system for adding custom
action bar buttons to the top menu, and demonstrates its use by adding a
cloud feedback button. The changes include defining a new
`ActionBarButton` type, updating the extension system to support action
bar buttons, creating a Pinia store to aggregate buttons from
extensions, and updating the UI to render these buttons in the top menu.
The cloud feedback button is now conditionally loaded for cloud
environments.

**Extensible Action Bar Button System**

* Defined a new `ActionBarButton` interface in `comfy.ts` for describing
buttons (icon, label, tooltip, class, click handler) and added an
`actionBarButtons` property to the `ComfyExtension` interface to allow
extensions to contribute buttons.
[[1]](diffhunk://#diff-c29886a1b0c982c6fff3545af0ca
<img width="1134" height="437" alt="Screenshot 2025-11-07 at 01 07 36"
src="https://github.com/user-attachments/assets/36b6145a-0b82-4f7d-88e8-f2ea350a359b"
/>
8ec269876c2cf3948f867d08c14032c04d66R60-R82)
[[2]](diffhunk://#diff-c29886a1b0c982c6fff3545af0ca8ec269876c2cf3948f867d08c14032c04d66R128-R131)
* Created a Pinia store (`actionBarButtonStore.ts`) that collects all
action bar buttons from registered extensions for use in the UI.

**UI Integration**

* Added a new `ActionBarButtons.vue` component that renders all action
bar buttons using the store, and integrated it into the top menu section
(`TopMenuSection.vue`).
[[1]](diffhunk://#diff-d6820f57cde865083d515ac0c23e1ad09e6fbc6792d742ae948a1d3b772be473R1-R28)
[[2]](diffhunk://#diff-45dffe390927ed2d5ba2426a139c52adae28ce15f81821c88e7991944562074cR10)
[[3]](diffhunk://#diff-45dffe390927ed2d5ba2426a139c52adae28ce15f81821c88e7991944562074cR28)

**Cloud Feedback Button Extension**

* Implemented a new extension (`cloudFeedbackTopbarButton.ts`) that
registers a "Feedback" button opening the Zendesk feedback page, and
ensured it loads only in cloud environments.
[[1]](diffhunk://#diff-b84a6a0dfaca19fd77b3fae6999a40c3ab8d04ed22636fcdecc65b385a8e9a98R1-R24)
[[2]](diffhunk://#diff-236993d9e4213efe96d267c75c3292d32b93aa4dd6c3318d26a397e0ae56bc87R32)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6626-Cloud-feedback-Extension-2a46d73d36508170bd07f582ccfabb3c)
by [Unito](https://www.unito.io)

src/types/comfy.ts

@@ -57,6 +57,32 @@ export interface TopbarBadge {
   tooltip?: string
 }
 
+/*
+ * Action bar button definition: add buttons to the action bar
+ */
+export interface ActionBarButton {
+  /**
+   * Icon class to display (e.g., "icon-[lucide--message-circle-question-mark]")
+   */
+  icon: string
+  /**
+   * Optional label text to display next to the icon
+   */
+  label?: string
+  /**
+   * Optional tooltip text to show on hover
+   */
+  tooltip?: string
+  /**
+   * Optional CSS classes to apply to the button
+   */
+  class?: string
+  /**
+   * Click handler for the button
+   */
+  onClick: () => void
+}
+
 export type MissingNodeType =
   | string
   // Primarily used by group nodes.
@@ -102,6 +128,10 @@ export interface ComfyExtension {
    * Badges to add to the top bar
    */
   topbarBadges?: TopbarBadge[]
+  /**
+   * Buttons to add to the action bar
+   */
+  actionBarButtons?: ActionBarButton[]
   /**
    * Allows any initialisation, e.g. loading resources. Called after the canvas is created but before nodes are added
    * @param app The ComfyUI app instance