Replaces the Mintlify setup (mint.json, docs.json, snippets) with a
standalone Fumadocs app in docs/: Next.js app router, meta.json nav per
section, its own bun install. Run with `just dev-docs`.
Content pass alongside the migration: core architecture, data model,
CLI, and networking pages rewritten around the daemon/source-store/
library split, new product-direction.mdx defining the product boundary,
new drive-catalog plan, and the physical-drives plan updated to
reference it. Whitepaper page retired.
The entry schema is the last thing standing from the old model and nothing
needs it. These cover the cutover, the destination written as though built, and
the hazards for work landing next to it.