CB-200: refactor high-complexity functions below grade A

[noahgift]

pmat comply check finding: 3 functions below A — need refactoring

Found by /kaizen continuous improvement cycle.

[noahgift]

Progress update: Top 2 highest-complexity functions refactored:

1. distill.rs run_text_generate(): 27 → <15 (6 helpers extracted)
   Commit: 20ff9bf
2. cbtop_report_tui.rs run_tui(): 24 → 8 (9 focused functions)
   Commit: 08ab3ae

Remaining: 37 warnings with scores 16-19 (near threshold). These are lower priority — the two P0 offenders (27 and 24) are resolved.