Gate selection and candidate filtering

Gate 4: consume analysis and emit candidate selection

Filtering and ranking candidate solutions at the gating step when analysis is complete.

• · project state
• · analysis artifacts
• · creative brief

• · selects_candidates.yaml file
• · project state updated
• · progress.json incremented

• · runTriage()
• · project_state.yaml
• · creative_brief.yaml

• · analysis_gate ready or partial_override
• · 01_intent/creative_brief.yaml exists
• · project_state.yaml writable

• · analysis_gate not ready → refuse to continue
• · missing creative_brief.yaml → stop with error
• · project_state.yaml locked → report and wait

• · Gate 4 only (enforced phase)
• · analysis_gate readiness check
• · contract validation (artifact presence)
• · state.yaml update on success