#95 PR-6 — Follow-up chains (decision_answers + parent_answer_id)

You are being dispatched from flower Brief #122: #95 PR-6 — Follow-up chains (decision_answers + parent_answer_id)

Recall pointer:
- Use recall_brief with id 122 for the full folder if you need provenance.

Target:
- project: flower (/Users/mikeferrara/Documents/code/flower)
- branch: flower/122-pr6-follow-up-chains
- worktree: not specified
- kind: fresh

Current brief spec:
## PR-6 — Follow-up chains (decision_answers + parent_answer_id) (child of #95)
Introduce `decision_answers` (typed answer rows, self-FK lineage). Backfill one row per already-answered
decision. Rewire `answer()` to write a row + keep the denormalized answer. `parent_answer_id` on
`decisions`. Threaded UI ("follow-up to your answer" quoting the parent) in the stream + flyout.
Deps: PR-1 (#117, answer path) + PR-4 (#120, flyout thread view). Design ref: #95 §5.2 / §8.
`php artisan test` green + pint. `Brief: #122` trailer.

Recent/key trace events:
[1] participant_joined flower-refine: (no body)
[2] note_added flower-refine: Child of #95. PR-6 of the 9-PR plan (§8 of the #95 design doc). Full spec via brief_update_spec.
[3] plan_proposed flower-refine: ## PR-6 — Follow-up chains (decision_answers + parent_answer_id) (child of #95)
Introduce `decision_answers` (typed answer rows, self-FK lineage). Backfill one row per already-answered
decision. Rewire `answer()` to write a row + keep the denormalized answer. `parent_answer_id` on
`decisions`. Threaded UI ("follow-up to your answer" quoting the parent) in the stream + flyout.
Deps: PR-1 (#117, answer path) + PR-4 (#120, flyout thread view). Design ref: #95 §5.2 / §8.
`php artisan test` green + pint. `Brief: #122` trailer.
[4] parent_set flower-refine: Grouped under epic #95.
[5] dependency_added flower-refine: Now depends on #117 (#95 PR-1 — Tracer: decisions spine (standalone confirm: ask→board→answer→pull→ack)).
[6] dependency_added flower-refine: Now depends on #120 (#95 PR-4 — "View more": flux:modal flyout + /decisions/{decision} page).
[7] status_change flower-refine: (no body)
[8] link_added flower-refine: (no body)
[9] link_added flower-refine: (no body)
[10] link_added flower-refine: (no body)
[11] participant_joined flower-120: (no body)
[12] unblocked flower-120: Unblocked — #120 reached complete.

Recommended linked context:
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            "name": "flower-refine — reset handoff (2026-07-03 #2)",
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            "name": "flower-refine — reset handoff (2026-07-04)",
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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: #122` to every commit for this brief so flower can exact-link commits back to the brief.