Fold the 5th GCP false-negative closure (plugin 1025 pure-ADC googleapis
auth) into the CE 0.2.1 docs and add the Task-12 live-validation results
(K1/K2 fired live; Dim4-6 confirmed running; no-false-clean invariant
held). Docs-only; version stays 0.2.1; plugin count 28; all six matrices
UNCHANGED.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>