* refactor(resilience): remove Cronbach alpha, add imputationShare confidence
Remove cronbach_alpha from proto (field 5 reserved) and all response
builders. Replace with imputationShare (field 9): the fraction of
weighted score from imputed (not observed) data.
lowConfidence now triggers on averageCoverage < 0.55 or
imputationShare > 0.40, replacing the unstable Cronbach-based gate.
weightedBlend() return type extended with observedWeight/imputedWeight
for provenance tracking through the scoring pipeline.
* fix(resilience): version cache key + fix IMF proxy imputation classification
1. Bump resilience score cache key to v2 to avoid serving stale
cached responses missing imputationShare after deploy.
2. Add explicit `imputed` flag to WeightedMetric so proxy data
(real IMF inflation with lower certaintyCoverage) is classified
as observed, not imputed. Only synthetic absence-based scores
count toward imputationShare.
2edcdeee06
