swink-agent 0.7.8

Core scaffolding for running LLM-powered agentic loops
Documentation
## What

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## Why

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## Test plan

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- [ ] `cargo test --workspace` passes
- [ ] `cargo clippy --workspace -- -D warnings` passes
- [ ] `cargo fmt --check` passes
- [ ] Relevant live/ignored tests run manually (if touching adapters)
- [ ] Added regression test for bug fixes

## Notes for reviewer

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