Install was at line 517 of 969, under the boot sequence, the snapshot lifecycle and
the release process. Someone deciding whether to trust this with their backups should
not have to scroll past any of that.
README is now 211 lines: what it does, the minimum version, install, the support
matrix, updating, uninstall. Everything else moved to docs/ (nested snapshots, how it
works, recovery, CLI, releasing).
A test enforces it: every internal link resolves, Install stays near the top, and the
README does not grow back. Moving Markdown breaks cross-references -- it broke eight
of them here, including one in a recovery doc, where the person following the link is
by definition already having a bad day.
