20260910-0135-product-tree-and-sidebar Reorganise product docs per product line and drop the sidebar

• status: completed
• priority: P1
• owner: claude/session-pages
• createdAt: 2026-09-10 01:35

Description

Two navigation changes to the docs site, requested together:

1. Give every product line its own directory under bizplan/product/ so later documents for one product are added next to its specification instead of into a flat 28-file folder.
2. Remove the site sidebar (option A) and navigate through index pages instead.

Acceptance criteria:

• Each product line has a directory; X01/X02 live in a shared directory.
• No sidebar remains in the VitePress config and .vitepress/sidebar.mts is deleted.
• bizplan/index.md and bizplan/research/index.md exist in both languages and list their sections.
• bun run docs:build passes with dead-link checking enabled.

ActiveForm

Reorganising product docs per product line and dropping the sidebar.

Dependencies

• blocked by: (none)
• blocks: the pending language decision (which documents keep an English version)

Notes

• Cross-references between product documents are bare filenames in backticks (about 1450 of them), not Markdown links, so keeping the filenames stable makes the move nearly free.

• Markdown links to product files exist almost only in bizplan/product/index.md and its Chinese mirror (14 lines each), plus 3 references from two research documents.

• complete: Product tree and sidebar removal shipped