Draft Introduction via ja-drafter/review/translate pipeline ...

Writes sections/1_introduction.tex through the documented workflow:
Japanese draft (drafts/ja/1_introduction.md), fact-check + content
review against the Notion source of truth, then English translation.
Centers the section on the proposed KSCNet architecture; open claims
without a source yet are left as inline [citation needed] markers.
Also documents the pipeline itself in CLAUDE.md.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Number section files to match reading order ...

sections/*.tex renamed to 1_introduction.tex .. 6_conclusion.tex so the
directory listing sorts in the same order they're \input from main.tex.
No 0_abstract.tex: the abstract must stay inline in main.tex (mdpi.cls
reuses it as PDF pdfsubject metadata, which \input breaks), and a
drafting-only file would just duplicate it with a risk of drifting out
of sync, so CLAUDE.md now says so explicitly.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>