feat: redesign Polish around simplify reviews

[dkstm95]

What changed

• Redesign Polish around independent cleanup scouts and a fresh adjudicating finisher.
• Add code-specific lenses for reuse, simplicity, efficiency, and abstraction fit.
• Support both bounded local edits and explicit review-only runs while keeping bug fixes, feature work, migrations, and broad sweeps out of scope.
• Update the English and Korean documentation, plugin metadata, generated package inventory, and release checks.
• Prepare Hope 2.1.0 in the four public version files.

Why

The previous Polish workflow preserved completed work but used a single worker and did not provide the focused cleanup discovery or exact current-change targeting associated with simplify-style workflows. This combines those strengths with evidence-based adjudication and small, behavior-preserving verification.

Impact

Polish can now simplify named work products or current repository changes, reject speculative cleanup, apply one coherent improvement pass, and verify only the affected boundary. Existing feature identity and preservation principles remain intact.

Release decision

minor → Hope 2.1.0. This adds a backward-compatible capability to the packaged Polish Skill.

Validation

• npm run check — 189 tests passed after version preparation
• npm run plugin:dev:install — Hope 2.0.0 installed and verified before version preparation
• Polish skill validation passed
• git diff --check passed
• Forward code evaluation reused an existing helper and passed targeted tests
• Forward review-only prose evaluation produced cleanup recommendations without changing the source file