feat(tools): scope operation journal identity by turn

[luoye520ww]

Summary

Replacement implementation for the rejected KunAgent#692 operation-journal direction.

Problem

The previous rejected design keyed operations by threadId + callId. Compatibility model paths can produce fallback call ids such as call_1 across multiple turns in the same thread, causing unsafe result reuse.

Changes implemented

• Add kun/src/reliability/operation-journal.ts with a turn-scoped identity:
  • threadId
  • turnId
  • callId
  • toolName
  • argsHash
• Add stable argument hashing with sorted object keys.
• Integrate the journal into LocalToolHost after approval/pre-hook/read/sandbox checks and before tool execution.
• Reuse only exact completed identities.
• Mark failed executions as failed and aborted executions as unknown.
• Add regression tests for:
  • same thread + different turn + fallback call_1 not colliding;
  • same exact identity reusing completed result;
  • same call id with different args not reusing.
• Removed the non-code .kun/review-plans file from this PR scope.

Important review blocker

The current LocalToolHost diff appears to include an unintended behavior regression around user_input / request_user_input and create_plan default tool construction. Before this can go upstream, restore the develop-branch structured GUI user-input behavior and createCreatePlanTool integration while preserving the operation journal changes.

Validation to run locally

npm --prefix kun run typecheck
npm --prefix kun test
npm run typecheck
npm test

I could not run local commands from this environment, so this remains draft until CI/local validation passes.