fix(opencode): handle session.idle event for turn-end detection

[dipree]

Summary

• OpenCode ≥1.3.x changed the session event model: session.status now only carries "busy"/"retry" (never "idle"), and a separate session.idle event fires when the agent finishes a turn
• The plugin only matched session.status with status.type === "idle", so turn-end hooks stopped firing entirely after upgrading from 1.2.x to 1.3.x
• Added session.idle as a fall-through case alongside session.status for cross-version compatibility

Root cause

Confirmed via diagnostic plugin logging. After the OpenCode 1.2.x → 1.3.x upgrade, the plugin's event handler receives:

// Many of these during a turn — status is always "busy", never "idle":
{"type":"session.status","props":{"sessionID":"ses_...","status":{"type":"busy"}}}
{"type":"session.status","props":{"sessionID":"ses_...","status":{"type":"busy"}}}

// One of these when the agent finishes — this is what the plugin needs to trigger turn-end:
{"type":"session.idle","props":{"sessionID":"ses_..."}}

The plugin checked props?.status?.type !== "idle" which always evaluated to true (since type is "busy"), so the handler broke out of every session.status event. The session.idle event that actually signals turn completion was unhandled.

Impact chain

1. turn-end hook never fires → PrepareTranscript never runs
2. opencode export <sessionID> never called → transcript file (.entire/tmp/<sessionID>.json) never created
3. Post-commit condensation fails silently: "transcript not found at .entire/tmp/<sessionID>.json: file does not exist"
4. Entire-Checkpoint trailer is still added to commits, but no session data is written to entire/checkpoints/v1
5. Checkpoint directories on GitHub are empty

Fix

Handle both event types as a fall-through case. session.idle has properties.sessionID directly, while session.status requires checking properties.status.type for "idle" (for ≤1.2.x backwards compatibility).

Test plan

• Diagnostic logging confirmed session.idle is emitted by OpenCode 1.3.2
• Diagnostic logging confirmed session.status only carries "busy" in 1.3.2
• Start an OpenCode session with the updated plugin
• Make changes and commit — verify turn-end appears in .entire/logs/entire.log
• Verify transcript file is created at .entire/tmp/<sessionID>.json
• Verify session condensed log entry with non-zero transcript_lines
• Push and verify checkpoint data appears on entire/checkpoints/v1 branch

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR updates the embedded OpenCode plugin template so Entire can reliably detect turn completion across OpenCode versions by handling the newer session.idle event in addition to session.status idle events.

Changes:

• Add session.idle as an additional switch case to trigger the turn-end hook.
• Branch per event type to extract sessionID from the correct event shape while keeping the sync hook execution behavior.

[Copilot]

Consider adding a regression assertion in the existing Go hook installation tests (cmd/entire/cli/agent/opencode/hooks_test.go) that the generated plugin content contains handling for both "session.status" and the newly-added "session.idle" event. Without a test, this compatibility fix could be accidentally removed or drift during future template edits without being caught by CI.