Issue: No-Projection Integration Lifecycle 2026-08-20

issue027 [ ] Manual integrations remain installed with no projection owner

Status: Closed by lifecycle verification on 2026-08-20.
Summary: A manual justify request that produces no spans, such as an empty or foreign-display-only buffer, still installs EKP change hooks and the substring filter even though auto-mode is disabled.
Expected vs Actual: Integrations should have one active owner: spans or auto-mode. Actual spans=nil still leaves the filter and hooks installed until a later change happens to trigger cleanup.
Related: ekp-buffer.el, plan_integration_lifecycle_20260728.md, task042.
Fix: Manual justification installs integrations only when a span or auto-mode owner exists.
Verification: Empty/foreign-only lifecycle ERT 2/2 and full buffer suite pass.
Resolved At: 2026-08-20.
Resolved By: Developer implementation and lifecycle verification.
Commit: Pending hardening commit.