Extract the Apple runner client from src/platforms/apple/core/runner into package ownership #2040

Post-#2038 extraction track (see the roadmap discussion on that PR). This is the largest single mass left in root platform code and has zero file overlap with the perf/trace migration, so it can run fully in parallel with it.

Scope

src/platforms/apple/core/runner/ (~344 kB source) — the XCUITest runner client: artifact cache, build/prewarm, request transport, session lifecycle. Destination: packages/platform-apple (or a dedicated package if its size and consumer set justify one — decide at the start and record the choice).

Current production consumers (19 files, enumerated 2026-08-26 on the #2038 head — re-derive with grep -rln "core/runner/" src before starting)

• Composition roots: src/platform-runtime-apple-application-tools.ts, platform-runtime-apple-automation-keep-hot.ts, platform-runtime-screen-recording-apple-runner-{host,transport}.ts, src/provider-device-runtime.ts
• Daemon (these are also the refactor(snapshot): assign and scope the Wave 4 shared presentation debt (#1739) #1983 shared capture/interaction debt files — coordinate, don't widen): snapshot-session.ts, selector-runtime.ts, request-recording-health.ts, session-device-utils.ts, request-platform-providers.ts, apple-runner-options.ts, server/daemon-runtime.ts
• Platforms: apple/{alert,interactions,interactor,doctor}.ts, apple/os/macos/desktop-scroll.ts, apple/os/tvos/remote.ts
• CLI: src/cli/commands/daemon.ts

Constraints

• Branch from main only after Migrate audio probe to platform runtime with durable resource lifecycle #2038 merges — it created src/platforms/apple/doctor.ts (a runner consumer) and this would conflict with it otherwise.
• Do not touch src/platforms/apple/core/perf.ts / perf-xctrace.ts or any session-perf* file — perf/trace is owned separately and in flight.
• ADR-0019 R13: the package façade must stay metadata-eager and implementation-lazy; the eager-closure budgets gate (src/__tests__/eager-closure-budgets.ts) pins this — move rows deliberately, never as slack.
• R11: new exported subpaths must be added in scripts/layering/package-boundaries.test.ts.
• Wire parity: runner request/response shapes are consumed by the Swift runner itself — byte-identical protocol, no drive-by changes.
• Precedents for the record format: refactor(snapshot): establish presentation ownership boundary #2005 / Extract snapshot policy from daemon to host-side facet (#1983) #2014 (ownership-slice extractions under refactor(snapshot): assign and scope the Wave 4 shared presentation debt (#1739) #1983), not a refactor(daemon): platform-free daemon — broader migration waves (successor to #1696) #1739 command unit — this moves mechanics, it migrates no command.

Acceptance

• Runner mechanics live under packages/, with root keeping at most composition-root wiring.
• The daemon platform-import scan (scripts/layering/daemon-modularity.ts baseline) shrinks or the residual edges are itemized.
• All layering/fallow/budget gates green; pnpm check:affected --run green; a refactor(snapshot): assign and scope the Wave 4 shared presentation debt (#1739) #1983-style record posted describing what moved and what deliberately stayed.