refactor(prose): task-map family folds onto existing batch forms (D7, stage 3)

[leeovery]

Stage 3 of the batching programme (design log: #504; base: #506). The task-map family — and the stage where contract C5 (cheaper-class-first) pays off: zero new engine code.

What

• scoping write-tasks: the 13-call register fence (11 sequential manifest sets to the same dotpath + lifecycle) and the separate per-task task_map registration loop collapse to topic start + one multi-field set carrying settings, position, the phase mapping, and every task mapping as field pairs + topic complete. This is the site whose shape the portal transcript showed being improvised as a shell for-loop.
• planning process-review-findings: each finding's task_map upkeep is now one call — multi-field set for added mappings, manifest apply (stage 2) when removals or mixed changes are involved. Per-finding commit cadence unchanged (each finding is its own approval + durability unit).
• author-tasks G reclassified in the census: its per-task commit is a deliberate durability boundary — a crash loses at most the in-flight task, and the plan resume gate reads the task position each iteration advances — and its manifest write was already a single batched set. By design, not a violation; collapsing it would regress recovery. Its dynamic git add argv remains stage-5 material.

Test plan

Prose-only: npm test 1552/1552, conventions lint 27/27, typecheck clean.

🤖 Generated with Claude Code

Stack

1. feat(engine): discovery-map add-batch — the harvest persists in one call (D7) #505
2. feat(engine): manifest apply — batched set/delete across one work unit (D7) #506
3. refactor(prose): task-map family folds onto existing batch forms (D7, stage 3) #507 👈 current
4. feat(engine): manifest set — two grammars, never mixed #508
5. refactor(prose): dump/read folds — subtree gets replace per-topic loops (D7, stage 5) #509
6. feat(engine): commit --plan — plan storage stages from recorded state (D7, stage 6) #510
7. fix: batching-stack review round — re-resolve rewired, guards symmetric, hardening pinned #512
8. fix: deep-dive round 2 — backbone rule flipped, pre-upgrade paths routed, flow bugs closed #513
9. fix(review-r3): engine hardening + crash-resume seams #514
10. feat(scoping): promotion routes through first-phase choice + bridge #515
11. fix(spec): pin the bugfix source name to the topic #516
12. fix(skills): gate-skip sentence accurate in gate-less phases #517
13. fix(review-entry): name the real upstream — specification and plan #518
14. fix(shared): strip triage-landing's unreachable superseded-research arm #519
15. feat(engine): refuse work-unit-level fields that shadow the phases tree #520
16. fix(discovery): first-written briefs join the full brief lifecycle #521
17. test(sim): pipeline simulation — engine driven end-to-end as a black box #522
18. fix(round-4): review findings — backfill keying, ratchet evasion, pull guard #523