Collocation: fold src/cli-schema into src/commands/schema, move batch-steps into src/commands/batch #2679

Purpose

Split out from #2677: the collocation plan posted there proposes a sequence of src/-touching file moves ("PR A/B/C") derived from the coupling/legibility measures that issue builds. Per a follow-up note, guard 9 on #2677 keeps that issue tooling-only (nothing under src//packages/ changes there), so the moves themselves belong in their own issue(s) rather than under #2677.

This issue tracks "PR A" from the plan: move 1 plus the bundled small move.

Scope

• Fold src/cli-schema/* (8 production + 8 colocated test files) into src/commands/schema/*. cli-schema is a standalone zone with Q ≈ 0, out/in flow 30, touching 29 of 39 families, and reader-condition legibility in the high-30s/low-40s depending on measurement — the plan's clearest "wrongly-a-family" candidate. It exists only to render the command facets commands/ already owns (refactor(cli-schema): orient the schema layer below commands #2543 declared that direction).
• Move src/cli/batch-steps.ts into src/commands/batch/batch-steps.ts (its only relative import and only real importer already live under src/commands/).
• Pure move, no behavior change: update every import site, the literal owner-files path in src/cli/command-explain.ts, the layering model's zone ranking (folded files resolve to the commands zone by directory, so the standalone cli-schema rank entry is dropped), fallow-baselines/health.json's path-keyed findings, and doc pointers (AGENTS.md, docs/agents/cli-flags.md).

Sequencing note

Per the same follow-up comment, this move should be rebased onto apex/module-shape-measures (the branch implementing #2677's Layer A/B tooling — pnpm coupling / pnpm legibility) so the before/after coupling and legibility numbers are attributable to the move alone, not confounded by the tooling landing separately.

At the time of writing, apex/module-shape-measures (86741f2) is 4 commits behind main, including #2665 (feat(cli): open --wait, flag suggestions, and refusals that name what to run), which also touches src/cli/parser/command-suggestions.ts — one of the files this move touches. Rebasing onto apex/module-shape-measures as-is produces a real conflict there (not just a mechanical one: apex is missing #2665's new suggestFlagFor/flag-suggestion code entirely, so the conflict isn't resolvable by picking a side without either dropping this move's import-path fix for that file or pulling in unrelated feature work). Rebasing cleanly needs apex/module-shape-measures refreshed against current main first.

Acceptance

• All import sites updated, no stray cli-schema or old batch-steps.ts path references
• pnpm lint, pnpm typecheck, pnpm format:check, pnpm check:layering, pnpm check:gate-manifest pass
• pnpm test:unit passes (pre-existing unrelated failures excepted)
• Rebased onto an up-to-date apex/module-shape-measures, with pnpm coupling before/after numbers in the PR description
• Base/head SHAs handed off for the pnpm legibility (Jev) before/after measurement, per the offer in Add report-only module-shape measures: placement legibility (Jev) and change-coupling modularity #2677 (comment)