Finish terminal side-effect authority migration

[nwparker]

Summary

Phase 3 slice 4 — completes the side-effect authority migration (design: docs/reference/terminal-side-effect-authority.md).

• Command Code output scraping moves to main: the chunk-boundary-safe detector runs per-PTY beside the title tracker on OSC-9999-stripped bytes, emitting command-code-working/command-code-done facts (banner self-arming preserved, plus runtime.noteTerminalSpawnCommand for the startup fast-arm since agent kind isn't known main-side). The 1500ms done settle timer deliberately stays in the renderer policy layer — it must consult the live store row that hook events also write (contract invariant 3)
• sidecar OSC-9999 dedup: background-launch and automation observers no longer double-write setAgentStatus for PTYs main covers; their pacing/automation responsibilities and byte access are untouched
• the parked watcher is now purely fact-driven under authority; the DECSET-2031 reply lives in a dedicated parked-terminal-mode2031-responder.ts whose byte subscription doubles as the Phase 4 delivery-interest signal
• headless hydration seeds prefer main's tracked title (the actual stale consumer from the synthetic reroute); daemon checkpoint lastTitle traced as write-only today and documented in the doc's Open Items

Parity improvement (pinned by test)

The old renderer raw-byte path's ANSI strip leaked OSC-9999 payload text into Command Code prompt-echo capture (working fired with an empty prompt; done never fired). Main's clean-data feed fixes this; the parity harness documents both behaviors.

Validation

• typecheck clean; oxlint + type-aware exhaustiveness clean
• 202 files / 2,688 tests green (orca-runtime, pty IPC, agent-hooks, full terminal-pane directory, background-session, automation observers, all of src/shared)
• e2e: terminal-attention, droid-notification, parking 3/3, hidden TUI restore 4/4 (14 total) + golden 2/2 on a fresh build

Cut-off

Independently mergeable; Phase 3 complete. Phase 4 (gating hidden PTY delivery in main) builds on the four enumerated subscribeToPtyData delivery-interest registrations.

Made with Orca 🐋

[stage-review]

Ready to review this PR? Stage has broken it down into 9 individual chapters for you:

	Title
1	Update migration documentation and open items
2	Define Command Code scrape facts and shared detector
3	Implement per-PTY Command Code detector in main
4	Wire spawn commands and test main detector
5	Handle Command Code facts in the renderer
6	Deduplicate OSC 9999 writes in sidecars
7	Refactor parked terminal mode-2031 responder
8	Prefer tracked title in hydration seeds
9	Other changes

_{Chapters generated by Stage for commit a23fedf on Jun 17, 2026 9:34am UTC.}

[nwparker]

Closing as superseded by merged PR #7214 (merge e84a8dd), which explicitly revived the complete term-speed-2 model/view chain into current main and then added newer scheduler, producer flow-control, snapshot, and reliability work. This old component/rollup branch no longer has an independent delta to rebase.