feat: add the concept write verbs to okf mcp

[chrishiguto]

Why

Raw concept edits can bypass Spec preparation, reserved-path safety, atomic index/log maintenance, and preservation of unmanaged content.

What

Adds create-concept and update-concept as thin adapters over the prepared-change module. Arguments become a change set, and OkfBundleChangeApplier.apply serializes preparation and the exact prepared commit under the shared bundle lock.

Malformed input remains a report-free tool error. A Spec-invalid candidate returns the stable Spec report and changes no file. Advisory-only candidates, including safe Unicode IDs, can commit. The server has no injected validator or executable rule-registration parameter.

The MCP annotations are explicit: create is additive and non-idempotent; update is destructive and idempotent; both operate only on the local bundle.

Reviewer's guide

Start with the write registrations and _write in lib/src/mcp/server.dart, then the protocol tests. The branch is restacked directly onto current main.

Prepared multi-file writes are rollback-backed for ordinary filesystem failures. They are not process- or power-loss crash-atomic because destination files are replaced independently; the README now states that boundary explicitly.

Testing

• dart format --output=none --set-exit-if-changed .
• dart analyze --fatal-infos
• dart test — 160 tests pass
• dart pub publish --dry-run — 0 warnings
• MCP protocol suite on Dart 3.4.0 — 10 tests pass
• Adversarial probes cover same-concept concurrent updates, two independent MCP writer processes, Unicode filesystem aliases, stable Spec refusals, and no-mutation error paths

Links

Fixes #12.

[chrishiguto]

RESOLVED — MCP writes use canonical apply

The MCP adapter now translates arguments into typed changes and delegates to the canonical serialized prepare/commit boundary through 0df28ac. It has no injected validator or strict write policy, commits advisory-only candidates, reports Spec refusals, and keeps malformed input in the tool-error tier.

Protocol and concurrency coverage pass with all four CI checks. This review no longer blocks the PR.