Task 080: ヘッダーナビの各話・総合分析ドロップダウン分離

Status: DONE

Motivation

Human directive: 「ヘッダーでは、各話分析と総合分析をそれぞれ選択できるやつがほしい」

Completed

• Split "分析レポート" dropdown into two separate dropdowns:

- 各話分析: EP01-EP05 episode page links

- 総合分析: Cross-episode, ship, science accuracy, communications, tech overview

• Added NavEpisode interface and episodes parameter to layoutHtml
• Updated all render functions to accept and pass navEpisodes
• Updated build pipeline to create navEpisodes from manifest
• All 965 tests pass, typecheck clean