TECH-9 · Reproducible setup/self-hosting guide

> Product/tech item from the dimensional diagnosis (**2026-07-03, v2**, section C).

### Action
Reproducible **setup/self-hosting guide** for partner institutions. *(Product/DevEx)*

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- **Priority:** 🟡 Medium
- **Epic:** #2503

Start by reading the linked epic #2503 and any existing setup or self-hosting documentation in the repository. The issue asks for a reproducible guide for partner institutions, so the work is done when a clean setup/self-hosting path is documented and can be followed from a fresh checkout without missing project-specific steps.

索引モデルが issue の本文から書いたものです。