Complete plan-builder P0 and P1 roadmap features

[jamil2018]

Summary

• complete all P0 plan-builder reliability features: unified preflight, expected-red capture, baseline recovery, lifecycle command center, exact execution preview, golden lifecycle certification, and bounded lifecycle telemetry
• complete all P1 authoring and observability features: validation context packs, coverage exploration, editable AST starters, registry-first recipes, runtime preparation, project notifications, live agent activity, operation receipts, evidence provenance, and revision-impact analysis
• surface the new guidance and audit evidence in the plan review workspace and coordinator event API
• sync canonical source into the create-appraisejs scaffold, update active lifecycle/coordinator docs, refresh Graphify outputs, and mark roadmap P0/P1 items implemented

Scope

This PR completes the roadmap's full P0 and P1 scope. P2 provider-native optimization features are explicitly excluded for now.

Milestones

• b62da7d1 unified agent preflight
• e7d42eb4 baseline evidence recovery
• d92d2abf lifecycle command center and exact preview
• 709857ed golden certification and lifecycle telemetry
• 952fbd0b validation authoring acceleration
• e005416c lifecycle insights and audit evidence
• a8dc92bb empty-plan validation-authoring compatibility repair

Validation

• focused P1 lifecycle/authoring tests: 63 passed in the final tranche; earlier focused suites also passed
• full root unit suite: 943/943 tests passed across 221 files
• appraisejs package: 126/126 tests passed
• golden plan-builder certification: 4/4 tests passed
• repository Cucumber command: passed; currently discovers 0 scenarios
• agent harness, coordinator-reference freshness, generated-artifact policy, and package-content checks: passed
• Fallow new-only and React Doctor pre-commit gates: passed
• Next.js production build: passed (7 known broad-pattern warnings)
• scaffold synchronization and Graphify source-graph refresh: completed
• GitHub Release CI: all jobs and the aggregate release check passed