Batch fix covering multiple modules: - P2-01: HandRegistry Semaphore-based max_concurrent enforcement - P2-03: Populate toolCount/metricCount from Hand trait methods - P2-06: heartbeat_update_config minimum interval validation - P2-07: ReflectionResult used_fallback marker for rule-based fallback - P2-08/09: identity_propose_change parameter naming consistency - P2-10: ClassroomMetadata is_placeholder flag for LLM failure - P2-11: classroomStore userDidCloseDuringGeneration intent tracking - P2-12: workflowStore pipeline_create sends actionType - P2-13/14: PipelineInfo step_count + PipelineStepInfo for proper step mapping - P2-15: Pipe transform support in context.resolve (8 transforms) - P2-16: Mustache {{...}} → \${...} auto-normalization - P2-17: SaaSLogin password placeholder 6→8 - P2-19: serialize_skill_md + update_skill preserve tools field - P2-22: ToolOutputGuard sensitive patterns from warn→block - P2-23: Mutex::unwrap() → unwrap_or_else in relay/service.rs - P3-01/03/07/08/09: Various P3 fixes - DEFECT_LIST.md: comprehensive status sync (43/51 fixed, 8 remaining) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>