Sprint 229 Plan: Constraint Synthesis Scaffolding

Goal

Produce concrete constraint scaffolding from incomplete specs.

Step 2184: Add canonical missing-constraint action mapping (security/perf/rollout/environment).
Step 2185: Generate remediation template snippets keyed to missing sections.
Step 2186: Persist suggested scaffold in machine-readable outputs.
Step 2187: Add baseline artifact capture under logs/taskitem_runs/spec_planning_*.
Step 2188: Add Sprint229IntegrationSummary.h.