간소화된 설명으로 README.ko.md 수정

[dkstm95]

수정된 내용은 Align, Toxic Review, Polish, Sweep 섹션의 설명을 간소화하고 명확하게 만듭니다.

Goal

• User result:
• Why it is needed:
• Not included:

Change

• Before:
• After:
• Important decision or tradeoff:

Safety

• Main risk or unknown:
• Ownership or cleanup rule, if relevant:

Validation

• Commands that ran:
• Checks not run:
• npm run check

Release

• Decision: none | patch | minor | major
• Version: unchanged | x.y.z
• Reason: