Track pending app release transitions

[kacy]

Summary

Track app release rows through an explicit pending-to-in-progress transition before terminal apply outcomes.

What Changed

• create local and cluster app release rows as pending
• move the shared apply executor to mark in_progress only when backend work begins
• simplify the shared apply lifecycle tests with common tracker helpers

Why

Phase 3 rollout-state work needs release lifecycle state to reflect execution timing instead of treating row creation as work already in progress.

Validation

• YOQ_SKIP_SLOW_TESTS=1 zig build test -Doptimize=ReleaseSafe -Dtest-filter='execute marks completed releases on backend success'
• YOQ_SKIP_SLOW_TESTS=1 zig build test -Doptimize=ReleaseSafe -Dtest-filter='recordAppReleaseStart stores app-scoped deployment metadata'
• YOQ_SKIP_SLOW_TESTS=1 zig build test -Doptimize=ReleaseSafe -Dtest-filter='app apply route preserves partially failed release metadata across reads'
• YOQ_SKIP_SLOW_TESTS=1 zig build test -Doptimize=ReleaseSafe -Dtest-filter='execute marks failed releases on backend error'
• YOQ_SKIP_SLOW_TESTS=1 zig build test -Doptimize=ReleaseSafe -Dtest-filter='app apply then rollback routes preserve release transition metadata'
• git diff --check