fix: Make current folder non-clickable in breadcrumb path bar

[soham04]

Description

Fixes the confusing UX issue where clicking the current folder in the breadcrumb path bar triggers a reload with a spinner that completes without any visible changes. This was especially confusing for new users who may not recognize it as a path bar.

Changes Made

• Added isCurrent flag to identify the last breadcrumb (current directory)
• Disabled the to prop for the current directory to make it non-navigable
• Disabled click handler for the current directory to prevent unnecessary reloads
• Simplified disableDrop logic to use the isCurrent flag
• Current folder now behaves as a label instead of an interactive button
• Fixes visual glitch with spacing between breadcrumb and "New" button

Testing

• ✅ Built successfully with npm run build in GitHub Codespaces
• ✅ No TypeScript/Vue compilation errors
• ✅ Code follows existing patterns in the codebase
• ✅ Logic verified: last breadcrumb is correctly identified and made non-clickable

Implementation Details

The fix uses a simple isCurrent flag based on the breadcrumb's index position. When isCurrent is true:

• The to prop is set to undefined (prevents navigation)
• The click handler returns undefined (prevents reload)
• The breadcrumb appears as a label rather than a clickable link

Fixes #55988

cc @nextcloud/designers @marcoambrosini @kra-mo

[soham04]

👋 Hi everyone, this is my first contribution to Nextcloud, so I want to make sure I’m testing things correctly.

I made this fix and verified that it builds successfully in GitHub Codespaces (npm run build worked fine).
However, I’d like to actually run the full Nextcloud UI locally to interact with the breadcrumb component and confirm everything visually.

Could you please share the recommended way to start the development environment for the server repo (e.g. via Docker or manual setup)?
I looked through the documentation under “Development environment” but just want to confirm what the maintainers typically use to preview UI changes.

Thanks in advance! 🙏
Really excited to make my first open source contribution here ❤️

[susnux]

Thank you for your PR!
But this behavior is intentional to reload the current folder without having to reload the full page.
In production its useful to have this to update the view after e.g. changes on your client.

Its also marked as this in the title of the button ("reload current view").

See discussion: #55988 (comment)