Ports the session reports that the bridge sends to v2 clients to the native
core, in src/v2-native/reports.ts: usage_update (context window, cost, model,
rate limit), the _meta.quota of each idle, Claude Code's warnings and client MCP
startup failures as notices, live and replayed compaction updates, the idle
compaction (/compact as running then idle, with no user_message), titles,
Task* plans, tool progress and memory recalls.
Shared with v1 instead of copied: the usage helpers move from acp-agent.ts to
session-usage.ts, the informational and MCP startup notices and the replayed
compaction move to session-notices.ts and context-compaction.ts, and
SessionTitles reads its session and agent through interfaces that
ClaudeAcpAgent already matches.
session/cancel now interrupts Claude Code also when no turn is open, as the
bridge does, which stops a turn Claude Code started but did not report yet.