- Inject '# Reporting outcomes' system block for Fable 5.1 / Mythos 5.1 models matching Claude Code 2.1.258 tengu_dapper_lagoon behavior. - Support both string-format and block-array system prompts for Fable reporting injection. - Add reconcileClaudeCodeFableModelAfterPayload to reconcile model additions when payload rules override model or thinking. - Reliably re-add reporting block if omitted after payload rules modify system blocks. - Drop injected thinking.display on Fable models when payload changes thinking type from adaptive to disabled. - Enhance payload rule path tracking with ancestor target matching in ApplyPayloadConfigWithTrackedPaths.