Simplify README, guides, and documentation comments

[lynnswap]

Summary

Rewrite the README and reference documentation to make installation, reviews, and updates easier to follow.

Details

• Keep setup steps in the README and move build and update simulation details to the existing guides.
• Simplify MCP arguments, results, and lifecycle explanations. Shorten design records while preserving their decisions and historical context.
• Rewrite all 17 Swift documentation comments with concrete descriptions of behavior and failure conditions. Executable code is unchanged.

Review focus

Check that the shorter explanations preserve API contracts, session access rules, and failure behavior.

Testing

• git diff --check passed.
• Checked local links, heading anchors, code fences, and TOML examples.
• Swift parsing passed for all nine edited Swift files; comparison with documentation comments removed confirmed no executable changes.
• Japanese prose lint and reading-load checks reported no findings.
• Codex review against origin/main completed with no findings (job BA70B004-50D9-4FD4-8041-E733733B1068).

Package and app test suites were not run for this documentation-only change.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-03T09:54:31.085705Z	82fa42e	PR opened
🔒 Security Review	✅ Completed 2026-10-03T09:55:26.971340Z	82fa42e	PR opened

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