Reconcile daemon_register_expected placeholder with flower:daemon-checkin (fix duplicate roster rows)

You are being dispatched from flower Brief #131: Reconcile daemon_register_expected placeholder with flower:daemon-checkin (fix duplicate roster rows)

Recall pointer:
- Use recall_brief with id 131 for the full folder if you need provenance.

Target:
- project: flower (/Users/mikeferrara/Documents/code/flower)
- branch: choose an appropriate branch
- worktree: not specified
- kind: fresh

Current brief spec:
(no spec yet)

This is a direct request, not a fully-specced plan. If it's clear, resolve it. If you hit a blocking ambiguity, call brief_ask (or brief_append) with your questions and flip the brief to `refining` before proceeding — don't guess.

Recent/key trace events:
[1] participant_joined flower-orchestrator: (no body)
[2] note_added flower-orchestrator: Split out from Brief #97 item 2 (charter review) — the CODE fix (kept separate from #97's charter-text changes). Also relates to the flower_feedback mcp_issue on duplicate roster rows.

PROBLEM (observed 2026-07-03 on the refine daemon): a `daemon_register_expected` placeholder row (for a role+project) and the `flower:daemon-checkin` command's check-in do NOT reconcile — the command creates a SECOND, separate roster row instead of adopting the existing `expected` placeholder. Result: a stale null-id placeholder row (#8) coexisting with the live correct row (#9) for the same daemon. Witnessed again this session: at takeover there was an `expected` orchestrator placeholder (daemon 11) that my checkin filled correctly, but the refine role had a stale null-id placeholder (#8) + live row (#9).

FIX: when `flower:daemon-checkin` (the command / DaemonCheckin path) runs, it should ADOPT an existing `expected` placeholder for the same (role, project) — updating that row with the resolved solo_process_id/session_id/context — instead of inserting a new row. Alternatively/additionally, `daemon_register_expected` should be keyed so a subsequent command-checkin updates it. Ensure no duplicate (role, project) rows result; a placeholder with null ids should be adopted by the first matching real checkin. Consider a one-time cleanup/merge of any existing stale null-id placeholder rows.

VERIFY: a test proving register_expected(role,project) → then a command-style checkin for the same (role,project) UPDATES the placeholder row (fills ids) rather than creating a 2nd row; roster shows one row per live daemon. `php artisan test` green; `./vendor/bin/pint`. `Brief: #<this-id>` trailer. Backend → Codex.
[3] participant_joined operator:mike: (no body)
[4] status_change operator:mike: (no body)
[5] link_added flower-orchestrator: (no body)

Recommended linked context:
{
    "todos": [],
    "scratchpads": [
        {
            "id": 346,
            "solo_scratchpad_id": "1026",
            "name": "Orchestrator HANDOFF — flower build (live state)",
            "archived": false,
            "revision": 79
        }
    ]
}

Execution notes:
- Treat the brief as the source of truth.
- Keep work scoped to this dispatch request.
- Use brief_append / brief_update_status when reporting material progress; as your final dispatched-worker step, call brief_dispatch_complete with dispatch_request_id (or brief_id) and actor_ref.
- Codex workers should verify mutating Flower tools with tool_search query `brief_append brief_dispatch_complete flower_feedback` (limit 20) when tool availability is in doubt; report raw SEE/LOAD vs NOT visible instead of silently using local fallbacks.
- Add a git commit trailer `Brief: #131` to every commit for this brief so flower can exact-link commits back to the brief.