refactor: centralize component ownership and generation disposal

[smiggleworth]

A component could be disposed repeatedly during reentrant cleanup, retain a child scope after a strict cleanup failure, or attach a lifecycle callback's returned cleanup after its lifetime had ended. Navigation also copied and reset component fields itself.

This change gives each lifetime one runtime ownership record and one disposal path. Component and keyed/control scope cleanup, resource/watch/query attachments, and cancellation use that owner. Lifecycle settlement captures its invoking lifetime, renderer reuse rejects disposed owners, and root preparation/rollback/retirement moves into runtime capabilities. The compatibility adapter preserves published owner properties and callback/readable-map identity through backed views, including extension-created records.

Validation:

• Formatting, lint/typecheck, build, public types, and publint pass.
• 238 unit, 53 repository-check, 1,533 jsdom, and 53 tests in each of Chromium, Firefox, and WebKit pass.
• Packed candidate and published 0.2.4 consumer fixtures pass (14 tests plus both TypeScript compiler checks).
• Three baseline and three candidate benchmark captures against ffa0ff4 pass all 19 touched rows: every capture meets the quality rules and every median change stays within 5%. The largest slowdown is 4.55% for table truncation. Full per-run statistics and provenance are in docs/benchmarks/core-ownership-8847810.json; no optimization claim.

Stage 3 of the core consolidation series. Renderer range ownership and the shared commit coordinator remain the following stages.