Local plugins incorrectly blocked from update UI

Bug Description

When trying to mark plugins to update via the plugin management UI, local plugins show an error:

Local plugins cannot be updated remotely. To update, modify the source at: ./plugins/feature-dev

<img width="1271" height="661" alt="Image" src="https://github.com/user-attachments/assets/f08d7eff-ffad-4c41-9ce5-f2e7fb918e98" />

Expected Behavior

Local plugins should either:

1. Not appear in the "update available" list if they can't be updated remotely, or
2. Allow some form of update action (e.g., pulling latest changes if it's a git repo)

Actual Behavior

Local plugins are shown as having updates available, but selecting them results in the error above.

Environment

• Platform: macOS