New e2e/fleet.spec.ts with a method- and URL-aware /api/fleet/** mock that
holds mutable state so operator actions and budget toggles reflect in
follow-up GETs. Covers: fleet overview (factory cards + recent jobs), jobs
table + stage filter, job detail requeue (stage building->queued) with the
SSE-driven Live badge, and budget pause/resume. All 4 specs green.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
