Removes the BROAD_SCOPE_FLAG_VERSION/decideBroadScopeFlag pipeline, the triage.ts call site that wrote `broadScopeFlag` source metadata and emitted task:broad-scope-flagged-at-triage audit events, the DatabaseMutationType enum entry, the diagnostic doc section, and the associated unit + reliability-interaction tests. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>