Task 384: Communications Per-Episode Delay Bar Chart

Status: DONE

Summary

Add a per-episode communication delay range bar chart to communications.md. Currently only has 1 timeseries chart (comm-delay-timeline). The bar chart will show min/max one-way light delay to Earth for each episode, making the escalating isolation immediately visible at a glance.

Rationale

• CLAUDE.md: "Diagrams and graphs for clarity" — more figures are better than fewer
• communications.md has only 1 chart among all summary reports
• The delay ranges are in a table but not visualized as a bar chart
• Complements the existing timeseries with an episode-level summary view