[Feature]: Side questions without polluting thread context (Codex /side equivalent) #9274

Feature request

It would be useful to have an equivalent of Codex's /side command: a way to ask a quick side question using the current thread's context, without adding that question or its answer to the main thread's subsequent context.

Example

While an agent is working in a long thread, I might want to ask:

Why did you choose a mutex here?

I want the side question to understand everything that has happened in the current thread, answer it, and then let me continue the original conversation as if the side exchange had not happened.

Why a separate thread isn't equivalent

Creating a new thread avoids polluting the main thread, but it doesn't automatically inherit the exact conversational context of the current thread. The useful property of /side is the combination of:

• access to the current thread/context
• a temporary side conversation
• no pollution of the main thread's future context

A /side-style command or UI action in T3 Code would be very useful for this workflow.