fix(install): bake dconf, seed main, name ISO, display modes (#123–#126)

Batch of existing-bug fixes from Acer/XPS install findings:

- #123: HM pre-activate creates /run/user/$UID and prefers
  dbus-run-session so dconf no longer aborts the desktop bake
- #124: main-built ISOs seed ?ref=main; patch-template rewrites
  inputs.nomarchy.url from NOMARCHY_FLAKE_URL (was set but unused)
- #125: image.baseName → nomarchy-live-….iso (not nixos-live-…)
- #126: Display mode list sorted by pixel area; toast shows hyprctl
  size; TESTING notes QEMU fixed-window scaling illusion

Verified: V0 flake check, installer-safety, baseName eval, patch-template
flakeUrl rewrite, mode-sort fixture.

hosts/live.nix

@@ -2,7 +2,7 @@
 # without touching the disk. The live session bundles nomarchy-install
 # (gum + disko + mkFlake) for a real install; this target also lets you
 # test the distro end-to-end on real hardware before committing to disk.
-{ lib, pkgs, username, nomarchySrc, ... }:
+{ lib, pkgs, config, username, nomarchySrc, ... }:
 
 let
   # ISO boot branding: the Nomarchy monogram recolored to the palette accent,
@@ -84,6 +84,11 @@ in
   isoImage.edition = lib.mkForce "live";
   isoImage.splashImage = isoSplash; # isolinux / BIOS
   isoImage.grubTheme = nomarchyGrubTheme; # GRUB / UEFI
+  # Filename: nixpkgs defaults image.baseName to "nixos-<edition>-…". Force
+  # nomarchy so result/iso/ is nomarchy-live-….iso, not nixos-live-….iso (#125).
+  image.baseName = lib.mkForce (
+    "nomarchy-${config.isoImage.edition}-${config.system.nixos.label}-${pkgs.stdenv.hostPlatform.system}"
+  );
 
   # The minimal-CD profile slims the image for a CONSOLE installer; this
   # ISO is the desktop, so re-enable what it strips. Above all