Playtest fixes — event grouping, target-type toggle, cameo cap, RoundSummary

[emp3thy]

Summary

Six fixes found while play-testing the Phase 4c slice 2 build — events display, launch targeting, and the round-summary "newspaper" page.

• Group repeated build events — the events screen showed "builds 1 small warhead" once per build. A new src/ui/util/eventGrouping.ts (groupPhaseEvents) counts builds per (leader, item) and renders "builds 3 small warheads". Aggregates by key rather than collapsing adjacent runs, so the human's interleaved build clicks group the same as the AI's item-grouped buildToward output.
• Sum impacts per attacker — the events screen now collapses multiple ImpactPeople/ImpactInfrastructure hits from one attacker on one target into a single "Carnage ─ 6M deaths (from IL)" line.
• Target-type toggle bug — flipping a target's people/infra toggle did not rewrite the targetType of launches already queued at that target, so a strike could land as people after the player switched to infra. The toggle now retargets every queued launch for that leader.
• Cameo cap — the "FROM CLACTON" Disparage cameo rolled per impact (~17.5% each), so multi-impact rounds produced several. Capped at one per round.
• RoundSummary subhead — reported the single largest strike instead of the per-attacker total ("for 6M" when the player hit for 12M across two strikes). Now sums deaths per attacker→target pair.
• RoundSummary stats — each leader's row on the round-summary page now shows population and factory counts (👥 25M · 🏭 8).

Test Plan

• npx tsc --noEmit — clean
• npm run test:run — 298/298 pass across 43 files (13 new tests: event grouping, the target-type retarget, the cameo cap, the subhead summing)
• Cameo-cap test confirmed red before the fix

🤖 Generated with Claude Code

[github-actions]

🔴 Claude BugBot Analysis

Found 1 potential bug in this PR.

medium: 1

One bug found: the plan document's chump planner spec code omits the ?. optional chain operator when reading .alive from state.leaders[t], inconsistent with all other planners and risking a TypeError if any cast member's leader record is undefined. All other actual source code changes (cameo cap in resolution.ts, event grouping utilities, target-type retargeting in Planning.tsx, pickSubhead aggregation) are correct.