Add configuration option to control default expand/collapse state of tool output blocks

Feature Description

Add a configuration option to control whether tool output blocks (thinking blocks, context blocks) are expanded or collapsed by default in the terminal UI.

Currently in v0.26.24+, these blocks are collapsed by default to prevent "streaming flicker" and keep the UI clean. While this is a good default, some users prefer to see the full output without manually toggling with Ctrl+O each time.

Proposed solution:

• Add a defaultExpandOutput boolean option to ~/.commandcode/config.json
• Default value: false (current behavior)
• When set to true, tool output blocks would be expanded by default

Use Case

This would benefit users who:

• Need to see the full AI reasoning/context for debugging or learning purposes
• Work in environments where manually expanding blocks adds friction to their workflow
• Prefer transparency in AI interactions and want to review all outputs
• Are reviewing complex multi-step operations where collapsing hides important context

Additional Context

This is a feature request stemming from the v0.26.24 release which intentionally collapsed these blocks by default. The current workaround is using Ctrl+O to toggle, but a configuration option would provide flexibility without requiring action on every session.

Priority: Important for my workflow

まず、~/.commandcode/config.json の設定処理と、ツール出力ブロックおよび Ctrl+O の切り替えを制御するターミナル UI のエントリポイントを見つけます。現在の折りたたまれたデフォルトを維持したまま defaultExpandOutput の動作を追加し、それを true に設定すると、thinking ブロックとコンテキストブロックが展開された状態でセッションが開始されることを確認します。