refactor(web): split large workflow pages and domain API contracts

[TusanHomichi]

Evidence

The 2026-09-05 continuation audit (PR #55, head 3d87379) found concentrated web ownership:

• web/src/routes/drafts/[id]/+page.svelte: 1,585 lines, covering draft editing and the subsequent record workflow.
• web/src/routes/enrollments/[id]/+page.svelte: 1,284 lines, covering enrollment and its related workflows.
• web/src/lib/api.ts: 1,271 lines, containing the shared request/error boundary alongside program, user, enrollment, training-session, draft, finalized-record, signoff, and export contracts.

The audit's existing browser scenarios passed. This is a maintainability follow-up, not a claim of a demonstrated UI regression. No existing open or closed issue owns the decomposition.

Proposed ownership and scope

• Extract cohesive workflow sections into domain components as each page next changes. Keep route loading/coordination in the page and give editing state/autosave one explicit owner; do not duplicate state across fragments.
• Separate domain-specific API contracts/functions from the shared request, session, and typed-error transport. Preserve compatibility imports if needed; avoid generic schema-driven UI or new client-side authorization authority.
• Start the implementation PR with a concrete move/new-owner/impact/test plan. Proposed section boundaries must be reviewed against current code, not treated as an approved design.
• Coordinate with Draft workspace: keep the losing writer's text visible after a stale-save reload #34 (stale-save recovery) and Trainees cannot view their own task signoff history in the web interface #49 (trainee signoff UI). Those remain separate behavior fixes and are not closed by moving code.

Acceptance criteria and proof

• Both pages and the API client have focused domain owners and no duplicated request/error policy or competing autosave state.
• Preserve route URLs, HTTP payloads, typed refusal handling, role/capability behavior, accessibility, and persisted record behavior. No schema or server authorization change.
• Preserve dirty edits, autosave/explicit-save behavior, and record/enrollment workflows through focused regression coverage appropriate to each extraction. Do not claim Draft workspace: keep the losing writer's text visible after a stale-save reload #34 repaired without its acceptance proof.
• Run npm check/build, all browser scenarios, and the CONTRIBUTING.md repository gates; update docs/development.md to route to the new owners.

Refs #53, #55. Source: docs/audits/2026-09-05.md, “Web ownership is concentrated.” Deliver in focused linked slices when these owners next change; no whole-interface rewrite is requested.

[TusanHomichi]

PR #66 completes the shared request/error transport extraction: web/src/lib/api/transport.ts now owns request, ApiError, and ApiErrorBody; legacy imports from api.ts remain compatible. Retention has a separate typed client and focused authority, policy, and hold components. HTTP behavior and existing call sites are preserved; the full local gates passed, including all nine browser scenarios.

This is a partial ownership slice. The existing domain clients in api.ts and the large draft/enrollment pages remain to be decomposed under this issue; #34 and #49 are unaffected.