Refine planner mode UI, logging, and history tracking

- Display coach feedback content (up to 25 lines) instead of just length
- Write GIT COMMIT entry to history before actual commit for better a...
- Implement single-line status updates during LLM processing with too...
- Display non-tool LLM text responses in planner UI
- Redirect all logs to <workspace>/logs directory instead of codepath
- Preserve TODO file in planner mode for history (prevent deletion)

Completed files:
- completed_requirements_2025-12-09_16-16-51.md
- completed_todo_2025-12-09_16-16-51.md

crates/g3-planner/src/history.rs

@@ -11,8 +11,6 @@ use std::fs::{self, OpenOptions};
 use std::io::Write;
 use std::path::Path;
 
-use crate::prompts;
-
 /// Format a timestamp for planner_history.txt entries
 /// Format: YYYY-MM-DD HH:MM:SS (ISO 8601 for readability)
 pub fn format_timestamp() -> String {