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.

flake.nix

@@ -51,16 +51,17 @@
           (nixpkgs.lib.concatStringsSep "\n"
             (builtins.attrNames nixos-hardware.nixosModules));
         nixpkgsPath = nixpkgs.outPath;
-        # Branch model: `main` is the development default; `v1` is the
-        # release pointer — the stable line for the NixOS 26.05 rewrite,
-        # advanced to main once a batch is tested (rolling, no tags). A
-        # future major bump would become `v2`. Installed machines track
-        # `?ref=v1` on `nix flake update`, not the forge's default branch.
-        flakeUrl = "git+${gitUrl}?ref=v1";
+        # Branch model: `main` is development; `v1` is the release pointer
+        # (advanced to main after human QA). Installs from a *main-built* ISO
+        # must seed `?ref=main` — seeding v1 while it lags hundreds of
+        # commits left machines with installer-written `nomarchy.hardware.*`
+        # that v1 does not have (#124). When cutting a release ISO from the
+        # v1 pointer, change both of these to "v1".
+        flakeUrl = "git+${gitUrl}?ref=main";
         # Future updates re-resolve from the forge (original); the install
         # itself resolves from the ISO store (locked = path) — fully
         # offline, even from a dirty-tree ISO.
-        originalNode = { type = "git"; url = gitUrl; ref = "v1"; };
+        originalNode = { type = "git"; url = gitUrl; ref = "main"; };
         lockedNode = {
           type = "path";
           path = self.outPath;