- modules/laptop.nix: add systemd-boot extraEntries for Windows Boot Manager
Chainloads $ESP/EFI/Microsoft/Boot/bootmgfw.efi. sort-key 'z_windows' puts
it after NixOS generations in the menu. Explicit entry works on all
systemd-boot versions; NixOS 26.05 'Yarara' may also autodetect on
shared ESP, in which case the duplicate is harmless.
- install.sh: guided dual-boot installer. Shrinks Win11 NTFS with ntfsresize
(no data loss), creates NixOS ext4 root, mounts shared ESP, runs
nixos-install with this flake. Idempotent except for the partition shrink.
- MIGRATION.md: new T490 + Windows 11 dual-boot section, with manual
fallback and NixOS 26.05 compatibility notes.