[hkrlogic]

Polish only, no new features. Fixes rough edges found in the end-to-end walk.

1. All write errors in one round. Tool argument schemas for create_item / update_item advertise types, required fields and limits (JSON Schema unchanged in shape: type, description) but no longer enforce them, so the SDK does not stop at its own first pass. The save check reports everything, merged with non-string values and the plain-General summary refusal, with the field list once at the end. Entity key and label problems are included.
2. No match is a normal result for list_items by q or entity_key (isError false, tells the agent to say it is not there).
3. Date order is checked only when both dates are real dates.
4. Shorter instructions/descriptions, safety rules kept (cite or say not there, published only, Review Lock / human-only publish and revert). Publisher (Review Lock, Policy) 5,662 → 2,975 chars; Review Unlock 6,335 → ~3,200; Reader key 1,563 → 1,299; create/update descriptions 669/637 → ~450/480.
5. charset=utf-8 on MCP responses (src/http/utf8-charset.ts).

Tests: new test/agent-polish.test.ts; updated three tests that asserted the old SDK-level rejection. Verified live on a fresh Compose stack over OAuth: one bad write returned 7 issues in one answer, no-match isError: false, content-type: text/event-stream; charset=utf-8.