Why: Freeze L1 skeleton KV keys and honest no-findings placeholder
so Backend can stop stuffing raw task text into progress cards.
Evidence: go test ./... -count=1
Impact: New TaskSummaryView helpers; findings[] still deferred to U2/U3.
Refs: fast-slow-channel-display-u1-plan W1
Co-authored-by: Cursor <cursoragent@cursor.com>
