Add Turns on the footer of the cli

### Describe the feature or problem you'd like to solve

As User I need a turns counter in immediate view so I know when to /compact

### Proposed solution

It is not practical to count my own turns when in the throws of solving the next corporate challenge using AI and agents .
I am focused on completing the challenge - not AI usage

In one of the recommendations by Claude Sonnet 4.5 - /Compact at turn 25-30 (not turn xx) → saves xxxM+ tokens per long session

Having the Turns easily in view will enable my cognitive memory to remember to /compact more frequently

### Example prompts or workflows

_No response_

### Additional context

_No response_

Start by locating the CLI footer rendering and the session state used by the /compact workflow; the issue does not name a file or test. Add a turns count to the footer and verify that it remains visible and reflects the user's turns during a session.

Written by the indexing model from the issue text.