docs: correct placement of development guide and update records ...

- Restored development_guide.md to docs/specification/.
- Updated journal to reflect the separation of specs and rules.

Docs: Separate technical specifications from project operational workflows

Docs/Chore: Establish bilingual (Japanese/English) issue policy and update dev guide

Docs/Chore: Implement manual issue closure reminder and update development guide rules

Refactor: reorganization of root and source directories and fix Error 1412