Referencing files with `@` now suggests apps first (even not-installed ones) before files, leading to frequent undesired installations of plugins I never asked to install

What version of the Codex App are you using (From “About Codex” dialog)?

Version 26.602.40724

What subscription do you have?

Plus

What platform is your computer?

Darwin 21.6.0 arm64 arm

What issue are you seeing?

Attempting to reference a file with @..., e.g. attempting to reference content.ts by typing @cont, results in Mac apps being the first suggestions, with file suggestions below.

Further, accepting an app suggestion (e.g. by pressing Tab) immediately leads to the plugin being installed (with no confirmation dialog before it's installed; simply hitting Tab) if the app requires that plugin. I then need to exit the chat, and go into Plugins to uninstall the plugin I never asked to install.

What steps can reproduce the bug?

1. Open a Codex chat in a workspace that has a content.ts file in it, with the Computer Use plugin not installed
2. Start typing @cont in the message input, to reference content.ts
3. Hit Tab (thinking it would just autocomplete to reference content.ts, or at most just reference the wrong thing in an easily fixable way while staying within the message input)
4. See a dialog appear: Adding Computer Use... plugin, followed by a notification at the top of the window: Computer Use plugin added
5. See that instead of content.ts, Contacts was referenced, and the Computer Use plugin was installed to support this reference, even though you never made any indication you wanted to install a plugin

<img width="733" height="206" alt="Image" src="https://github.com/user-attachments/assets/a872e670-dd99-4b6d-aec1-ec909ecf6061" />

=>

<img width="468" height="188" alt="Image" src="https://github.com/user-attachments/assets/f6eda493-d1b9-4977-9980-6159ac27da65" />

=>

<img width="260" height="53" alt="Image" src="https://github.com/user-attachments/assets/ab35f8a2-4fd6-48a8-b466-a620930d2299" />

=>

<img width="326" height="106" alt="Image" src="https://github.com/user-attachments/assets/026a8cc9-50f8-4582-bc6d-bc6ca6f7a505" />

What is the expected behavior?

Ideally, files and apps should be referenced by using different prefixes. Referencing a local file is entirely different from referencing an app and installing a plugin, and should involve different workflows that would never result in the user accidentally installing a plugin while simply attempting to reference a file.

At the very least, though, plugins should never be immediately installed from a simple autocomplete accept, without any intermediate confirmation step that the user actually wants to install a plugin.

Additional information

_No response_