fix(claude): finish compaction in ready state

[Yoonwoo-Ha]

Problem

Claude writes /compact completion as a synthetic user summary followed by local-command wrapper records. ChatMux treated the wrapper output as a new user prompt, so an idle compacted session stayed RUN, and rendered the full generated summary directly in the conversation.

Changes

• classify Claude compact-summary records as waiting_user without generating a reply-completion notification
• ignore Claude's internal local-command wrapper records during activity detection
• render compact summaries as a collapsed, localized disclosure
• defer mounting the summary Markdown until the disclosure is opened
• cover the activity sequence and collapsed/expanded rendering with regression tests

Verification

• replayed the observed Claude transcript sequence: waiting_user, terminal outcome none
• npm run verify
  • server tests: 1,842 passed
  • tmux/PTY tests: 50 passed
  • client tests: 731 passed
  • typecheck, lint, identity, Rust checks, and production build passed

[devswha]

Reviewed the full diff at head 69dd58c and verified locally on the PR branch: focused tests pass (external-session-activity 20/20, MessageComponent 8/8), CI green, base is current main. Server side classifies isCompactSummary user records as waiting_user without a reply-completion notification and skips local-command wrapper records during activity detection; client renders compact summaries as a collapsed disclosure with the Markdown body mounted only on open; messageTypes.compactSummary added across all 10 locales; regression coverage on both sides. isCompactSummary propagation was already on main (claude-sessions.provider), so this PR only adds classification, rendering, i18n, and tests. No action-boundary or identity changes — display/activity only. Merging.