Project timelines now accept a side-by-side human commentary per entry

What I did

Added a companion-file mechanism so every project-log entry can carry a parallel hand-written commentary, displayed side-by-side with the AI version.

What it looked like before

Project timelines (daeseon-ai, shadow-ai, dalkkak-ai, docvault) were entirely AI-written. The human author had no presence in them — readable but uniform, and not honest about the actual authorship split.

What I changed

A .human.mdx companion convention. Next to any <date>-<slug>.mdx, drop <date>-<slug>.human.mdx containing only the body (frontmatter ignored). On the detail page:

• Desktop (md+): two columns, AI on the left, "By hand" on the right, with a separator and a wider max-w-6xl container.
• Mobile: stacked, same labels.
• No companion: page is unchanged (single column, max-w-3xl).

The companion is filtered out of listProjectLogs so it doesn't appear as a standalone timeline entry — it's strictly an attachment to its sibling.

Files: lib/logs.ts (getHumanCompanion + the filter), components/LogBody.tsx (conditional two-column), both EN and KO log-entry routes.

What happened

Build passes; an entry that has a companion (zero exist yet — that's the next step) will render two-column.

What it doesn't do / what's next

• Companions are body-only — they can't override metadata. Fine for the use case ("my parallel commentary on the same event") but means a companion can't disagree with the entry's title or kind without editing the main file.
• An orphan companion (AI entry deleted) is silently ignored, not surfaced as a warning.
• The next step is purely content: drop a first real .human.mdx next to one of the existing AI entries (probably shadow-ai or dalkkak-ai) to see how it reads in the wild.

Commit

78368f2 — Add side-by-side human companion for log entries.