T2 of TASK-rectification-grounding-20260927 (product decision P1). The rectification 「重试(重新生成)」 was a blind agent.generate rewrite that persisted unchecked text (invented range / fit rate reproduced). Removed: the regenerate route, regenerate-turn.ts, the regeneration agent and its read-only tool set, the client regenerate action/state and the regenerating/canRegenerate props. ChatMessageActions renders the regenerate button only when onRegenerate is passed; ordinary consultation is unchanged. The DB function regenerate_agentic_rectification_turn is kept (AGENTS §7.6, retire in a later round). DESIGN.md / VOICE.md updated; source-contract tests follow with 原值/新值/原因 notes. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_017eEAG8HD3mm8gsKXgk8uU8