Overseer: wire AGENT_NOTIFY_SUMMARY emission for kimi / pi / remaining ACP

[heavygee]

Summary

Half B of overseer summary emission covers Cursor (transient .cursor/rules/hapi-session.mdc overlay, PR #86) and Claude / Codex / Grok / OpenCode (systemPrompt / developer_instructions / one-shot first-turn inject, PR #88). Hub deterministic fallback is PR #87.

Still uncovered for primary AGENT_NOTIFY_SUMMARY emission (they only get the hub first-line heuristic fallback today):

• kimi (cli/src/kimi/) — no systemPrompt / instruction channel wired yet
• pi (cli/src/pi/) — same gap
• generic ACP agents that are not cursor/grok/opencode — same removed-prepend gap (fix(cli): skill_lookup $name instruction prepended to Cursor user turns triggers prompt-injection false positive tiann/hapi#1095/fix(cli): stop skill_lookup $name user-turn prepend (prompt-injection FP) tiann/hapi#1096); need a flavor-appropriate non-user-turn channel

Next overseer phase needs full-fleet primary emission, not just Cursor + the four systemPrompt flavors. This issue tracks that remaining coverage.

Constraints (do not re-litigate)

• No user-turn prepend (upstream fix(cli): skill_lookup $name instruction prepended to Cursor user turns triggers prompt-injection false positive tiann/hapi#1095 / fork fix(cli): stop skill_lookup $name user-turn prepend (prompt-injection FP) tiann/hapi#1096 prompt-injection false positive).
• Prefer systemPrompt / developer_instructions / one-shot first-turn / ACP-native instruction channels — same discipline as feat(overseer): non-Cursor session-summary contract + debug relative dates #88.
• Benign "session tracking" copy; fork-only overseer.
• Opt-out remains HAPI_SESSION_SUMMARY_CONTRACT=0 once wired.

Acceptance

• kimi sessions emit parseable trailing AGENT_NOTIFY_SUMMARY (or documented why impossible + residual fallback only)
• pi sessions same
• any remaining generic ACP launcher path same or explicitly scoped out with kill-criteria
• tests + soup layer after feat/overseer-summary-flavors-and-dates
• emit vs fallback ratio remeasured post-ship (feeds the better-LLM-fallback rarity gate in docs/plans/2026-07-24-overseer-summary-emission.md)

Related

• Design: docs/plans/2026-07-24-overseer-summary-emission.md
• PR feat(overseer): emit AGENT_NOTIFY_SUMMARY from Cursor (Half B, piece 1) #86 Cursor overlay
• PR feat(overseer): deterministic per-turn fallback when no summary line (Half B, piece 2) #87 hub deterministic fallback
• PR feat(overseer): non-Cursor session-summary contract + debug relative dates #88 Claude/Codex/Grok/OpenCode systemPrompt + debug dates
• Epic context: overseer emission / fleet-overseer (Pre-flight: emission-contract empirical sniff #20 sniff, Step 2: Events table + worker emission #22 events, Step 2.5: Inbox substrate + dumb v1 ordering + operator-action logging #23 inbox)

Fork-only

Never upstream. Overseer is fork-private.