v0.4.0 - OpenCode v2 compatibility

v0.4.0 - OpenCode v2 compatibility

OpenCode v2.2.0 moved execution state out of session.status (and the v2 wire has no session.idle). This release keeps the same badge contract on both channels:

• v2 model switch - session.model.selected { model, previous } moves a session's badge instantly (same as v1's session.model.updated)
• v2 rate-limit back-off - session.retry.scheduled { at, attempt, error } paints the model amber and seeds the ? window from the provider's own resume epoch �t
• v2 execution lifecycle - session.execution.started / succeeded / failed / interrupted drive busy/idle; a failure without any back-off event in the chain earns no ? (regression guard for #10)
• Replay guard - durable v2 frames replayed after a reconnect can refresh bookkeeping but never resurrect liveness: no ghost ? on sessions that idled before the connection
• Back-off sweeper - a missed follow-up execution event can no longer hold a stale ? forever
• 24-test suite - 4 new v2 event tests ( est/v2-events.test.js)

Install: copy index.ts + lib.ts into ~/.config/opencode/plugins/model-badges/; badges rebuild on the next picker open.