fix mmb navigation when click starts on Vue nodes (#5921)

## Summary

Fixes https://github.com/Comfy-Org/ComfyUI_frontend/issues/5860
by updating Vue node pointer interactions to forward middle mouse button
events to canvas instead of handling them locally.

## Review Focus

Middle mouse button event detection logic using both `button` property
and `buttons` bitmask for cross-browser compatibility. Test coverage for
pointer event forwarding behavior.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-5921-fix-mmb-navigation-when-click-starts-on-Vue-nodes-2826d73d3650819688eec4600666755d)
by [Unito](https://www.unito.io)

---------

Co-authored-by: DrJKL <DrJKL@users.noreply.github.com>

knip.config.ts

@@ -23,7 +23,7 @@ const config: KnipConfig = {
       project: ['src/**/*.{js,ts}']
     }
   },
-  ignoreBinaries: ['python3'],
+  ignoreBinaries: ['python3', 'stylelint'],
   ignoreDependencies: [
     // Weird importmap things
     '@iconify/json',
@@ -32,7 +32,8 @@ const config: KnipConfig = {
     '@primeuix/utils',
     '@primevue/icons',
     // Dev
-    '@trivago/prettier-plugin-sort-imports'
+    '@trivago/prettier-plugin-sort-imports',
+    'stylelint'
   ],
   ignore: [
     // Auto generated manager types