[FEATURE] Plan mode to use own context like an agent so as not to use context from main workflow

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

I like plan mode and use it regularly. I often have a back and forth in plan mode and end up using many tokens. When it finally comes to switching to accept mode I am near the end of the context. It would be nice plan mode could somehow not eat into the coding context so when coding starts it has plenty of runaway.

Proposed Solution

Make plan mode behave like an agent wrt context use.

Alternative Solutions

_No response_

Priority

Medium - Would be very helpful

Feature Category

Interactive mode (TUI)

Use Case Example

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Additional Context

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