Add format_event_type() and calculate_duration() helpers to convert
raw timeline events into human-readable tables and metrics. RCA now
includes an Incident Timeline section and Incident Metrics (event
count, duration, time-to-root-cause). Postmortem replaces placeholder
timeline rows with real events, calculates impact duration, and
auto-populates What Went Well from evidence.
10 new Rust tests covering timeline rendering, duration calculation,
and event type formatting.
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