#1262 Claude settings json

Summary by cubic

Add a dedicated Claude hooks config and make hook commands non-blocking and more robust. Standardizes session/task automation, ensures .claude/settings.json is tracked, and fixes a missing trailing newline.

• New Features

  • Added .claude/settings.json with session and task hooks that call entire hooks claude-code ... (async, 30s).
  • Set env defaults: ANTHROPIC_DEFAULT_HAIKU_MODEL and ANTHROPIC_DEFAULT_SONNET_MODEL.
  • Denied reads to ./.entire/metadata/**; updated .gitignore to ignore .claude/* but track .claude/settings.json.

• Refactors

  • Made git-ai checkpoint claude --hook-input stdin run async to avoid blocking.
  • Guarded dcg calls with command -v dcg >/dev/null 2>&1 && dcg; removed unnecessary async on a dcg hook.
  • Kept existing timeouts (5s/15s) while improving reliability.