System closure delta: both apps vs. Portfolio-only vs. master

Companion to closure-delta.md (read that first for the master-vs-Portfolio comparison and method). This adds the k230-coherent-shell-both-files-apps configuration (k230.shell.filesAppNautilus = true), built with the same command against that configuration: nix build .#nixosConfigurations.k230-coherent-shell-both-files-apps.config.system.build.toplevel --max-jobs 1 --cores 6 --no-link --print-out-paths.

Store path: /nix/store/b2f6yqk428w599jcc7w6rcjawld85bp6-nixos-system-nixos-26.11.20260919.20b1ddd.

Result

	requisite paths	summed size
master baseline	1041	3.196 GiB (3,432,123,872 B)
Portfolio-only	1114	3.576 GiB (3,840,008,000 B)
Both apps	1154	3.704 GiB (3,976,704,760 B)
Nautilus’s marginal delta (both vs. Portfolio-only)	+40 net (54 new, 14 superseded)	+130.4 MiB (+0.127 GiB, +136,696,760 B)
Both apps vs. master	+113 net	+519.4 MiB (+0.507 GiB, +544,580,888 B)

Reading this

Nautilus’s own standalone riscv64 closure (docs/evidence/files-app/ task 2.3) is 1015.3 MiB — but almost all of that is gtk4/libadwaita and GStreamer’s default media backend, which Portfolio’s own presence in this system already pays for. What Nautilus adds on top of an already-GTK4 system is much smaller in bytes, and is itemized dependency-surface growth rather than raw size:

Device sync: libimobiledevice, libimobiledevice-glue, libusbmuxd, libplist, libtatsu (iOS-over-USB support Nautilus links unconditionally).
Network directory sharing: gnome-user-share, apache-httpd, apr/apr-util, mod_dnssd, cyrus-sasl.
Search/indexing: localsearch (Nautilus’s own search backend, distinct from the tinysparql library both apps already share).
Directory/LDAP/PDF/metadata: polkit, openldap, poppler-glib, poppler-data, libgxps, gexiv2, exempi, libgsf, libzip.
Desktop integration: libnotify, libcloudproviders, libosinfo+osinfo-db, gnome-autoar, gnome-desktop, libproxy, totem-pl-parser, glib-networking, nspr/nss, bubblewrap, libportal-gtk4.
Nautilus and its image-loader backend themselves: nautilus-riscv64-unknown-linux-gnu-50.2.2, glycin-loaders, libglycin, libglycin-gtk4, and k230-nautilus (this change’s launcher wrapper).

None of this is started as a running service by this change (no systemd user unit wiring for gvfs/tracker/localsearch/gnome-user-share) — see proposal.md’s non-goals. Nautilus falls back to plain directory reads without them; whether that is fast enough on this board’s single in-order core over a large directory is the coordinator’s own scroll/large-directory task (tasks.md 5.3), not measured here.