fix: shallow fetch event state checkout

[Takhoffman]

Summary

• Shallow-fetch ClawSweeper state in the targeted event-item publish path.
• Avoid full-history state repo fetches before publishing targeted re-review results.

Validation

• /Users/takayukihoffman/.codex/worktrees/20f9/clawsweeper/node_modules/.bin/oxfmt --check .github/workflows/sweep.yml

Refs #204

[clawsweeper]

ClawSweeper status: review started.

I am starting a fresh review of this pull request: fix: shallow fetch event state checkout This is item 1/1 in the current shard. Shard 0/1.

This placeholder means the worker is alive and reading the current context. I will edit this same comment with the actual review when the claws are done clicking.

Crustacean status: shell secured, claws on keyboard, evidence pebbles being sorted.