fedora-intune: fix boot issues, add Himmelblau variant

Fixes found by building and inspecting the image:

- Select the Intune authselect profile with-altfiles. Without it system
  users in /usr/lib/passwd (gdm, pipewire, mdatp) do not resolve and the
  login screen never starts. The build now fails if gdm does not resolve.
- Ship /opt as a plain directory (opt-usrlocal: root). Defender installs
  to /opt/microsoft/mdatp and keeps state in /var/opt/microsoft/mdatp;
  with the default /opt -> /var/opt symlink those were the same
  read-only directory. rpm-ostree still relocates /opt content to
  /usr/lib/opt, so finalize.d/60-opt-links links it back (only for images
  where /opt is a directory; fedora-cosmic/remote are unaffected).
- Run Defender's %post on first boot (mdatp-firstboot.service): in a
  compose /var is read-only and the machine GUID/state must not be
  shared. mdatp.service waits for it.

New image fedora-intune-himmelblau: the same workstation with Entra ID
sign-in through Himmelblau (Community Nightly packages), which joins the
device at the first sign-in and enrolls it in Intune (apply_policy)
instead of the Microsoft Intune app. Workstation, Edge and Defender
manifests move to images/shared so both images use them; build.sh copies
images/shared/*.yaml and CI builds both images in one matrix job.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

images/shared/defender.yaml

@@ -0,0 +1,46 @@
+# Microsoft Defender for Endpoint on Linux (mdatp), RHEL 10 build, from the
+# microsoft-rhel10 repo (shared/repos/microsoft.repo).
+#
+# mdatp's %post does the real install: units, SELinux module, and per-machine
+# state under /var/opt/microsoft/mdatp (machine GUID, definitions database,
+# logs). In a compose /var is read-only, and that state must not be shared
+# between machines anyway, so the %post is saved into the image and run once on
+# first boot by mdatp-firstboot.service. mdatp.service waits for it.
+#
+# Onboarding is per tenant and not part of the image: run the onboarding script
+# from the Defender portal on the device.
+
+repo-packages:
+  - repo: microsoft-rhel10
+    packages:
+      - mdatp
+
+packages:
+  # The %post is a bash script; Defender's inventory scripts and the
+  # onboarding script are Python.
+  - bash
+  - python3
+
+add-files:
+  - ["mdatp-firstboot", "/usr/libexec/mdatp-firstboot"]
+  - ["mdatp-firstboot.service", "/usr/lib/systemd/system/mdatp-firstboot.service"]
+  - ["mdatp-firstboot.conf", "/usr/lib/systemd/system/mdatp.service.d/10-firstboot.conf"]
+  - ["50-defender.preset", "/usr/lib/systemd/system-preset/50-defender.preset"]
+
+postprocess:
+  - |
+    #!/usr/bin/env bash
+    set -xeuo pipefail
+    # The %post wrote the units during the compose; fail the build if a newer
+    # mdatp stops doing that, rather than shipping a Defender that never starts.
+    for unit in mdatp.service mde_netfilter_v2.service mde_netfilter_v2.socket; do
+      test -f "/usr/lib/systemd/system/${unit}"
+    done
+    # rpm-ostree keeps /opt content in /usr/lib/opt until the commit.
+    for root in /usr/lib/opt /opt; do
+      pp="${root}/microsoft/mdatp/conf/selinux_policies/out/mdatp_service.pp"
+      [[ -f "${pp}" ]] && break
+    done
+    semodule -n -i "${pp}"
+    rpm -q --qf '%{POSTIN}' mdatp > /usr/libexec/mdatp-postinst
+    chmod 0755 /usr/libexec/mdatp-firstboot /usr/libexec/mdatp-postinst

images/shared/files/10-workstation-sshd.conf

@@ -0,0 +1,6 @@
+# Key-only SSH for local accounts (add keys to ~/.ssh/authorized_keys).
+PubkeyAuthentication yes
+PermitRootLogin no
+PasswordAuthentication no
+PermitEmptyPasswords no
+KbdInteractiveAuthentication no

images/shared/files/50-defender.preset

@@ -0,0 +1,4 @@
+# Defender: first-boot setup, the daemon and its network filter.
+enable mdatp-firstboot.service
+enable mdatp.service
+enable mde_netfilter_v2.socket

images/shared/files/50-workstation.preset

@@ -0,0 +1,3 @@
+enable gdm.service
+enable qemu-guest-agent.service
+enable sshd.service

images/shared/files/finalize.d/60-opt-links

@@ -0,0 +1,20 @@
+#!/bin/bash
+# Runs in the target root during `rpm-ostree compose image` (edition 2024
+# finalize.d hook). rpm-ostree relocates RPM content under /opt to
+# /usr/lib/opt. With `opt-usrlocal: root` /opt is a plain directory in the
+# image and nothing links it back, so link each vendor directory. Images on the
+# default (/opt -> /var/opt, linked by tmpfiles.d) are left alone.
+set -euo pipefail
+
+root="${PWD}"
+
+[[ -d "${root}/usr/lib/opt" ]] || exit 0
+if [[ -L "${root}/opt" || ! -d "${root}/opt" ]]; then
+  exit 0
+fi
+
+for dir in "${root}"/usr/lib/opt/*; do
+  name="$(basename "${dir}")"
+  ln -sfn "../usr/lib/opt/${name}" "${root}/opt/${name}"
+  echo "Linked /opt/${name} -> /usr/lib/opt/${name}"
+done

images/shared/files/mdatp-firstboot

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+# Finish the Defender (mdatp) install on first boot by running the package's
+# own %post, saved at build time: it creates the machine GUID, state, logs and
+# definitions database under /var and then enables and starts mdatp.service.
+set -euo pipefail
+
+MARKER=/var/lib/mdatp-firstboot.done
+
+[[ -f "${MARKER}" ]] && exit 0
+
+# mdatp.service only starts once the marker exists (10-firstboot.conf), and the
+# %post starts it, so create the marker first and drop it again on failure.
+touch "${MARKER}"
+if ! bash /usr/libexec/mdatp-postinst 1; then
+  rm -f "${MARKER}"
+  exit 1
+fi

images/shared/files/mdatp-firstboot.conf

@@ -0,0 +1,3 @@
+# Don't start Defender before mdatp-firstboot.service has created its state.
+[Unit]
+ConditionPathExists=/var/lib/mdatp-firstboot.done

images/shared/files/mdatp-firstboot.service

@@ -0,0 +1,15 @@
+[Unit]
+Description=Finish the Microsoft Defender for Endpoint install on first boot
+Documentation=https://learn.microsoft.com/en-us/defender-endpoint/microsoft-defender-endpoint-linux
+After=network-online.target
+Wants=network-online.target
+ConditionPathExists=!/var/lib/mdatp-firstboot.done
+
+[Service]
+Type=oneshot
+ExecStart=/usr/libexec/mdatp-firstboot
+RemainAfterExit=yes
+TimeoutStartSec=15min
+
+[Install]
+WantedBy=multi-user.target

images/shared/microsoft-edge.yaml

@@ -0,0 +1,7 @@
+# Microsoft Edge, from the microsoft-edge repo (shared/repos/microsoft.repo).
+# Conditional Access to Microsoft 365 web apps on Linux requires Edge.
+
+repo-packages:
+  - repo: microsoft-edge
+    packages:
+      - microsoft-edge-stable

images/shared/repos/microsoft.repo

@@ -0,0 +1,19 @@
+# packages.microsoft.com, limited with includepkgs to the packages the images
+# use, so nothing else from the RHEL repo can replace a Fedora package.
+
+[microsoft-rhel10]
+name=Microsoft Production (RHEL 10)
+baseurl=https://packages.microsoft.com/rhel/10/prod/
+enabled=1
+gpgcheck=1
+repo_gpgcheck=1
+gpgkey=https://packages.microsoft.com/keys/microsoft-2025.asc
+includepkgs=intune-portal microsoft-identity-broker mdatp
+
+[microsoft-edge]
+name=Microsoft Edge
+baseurl=https://packages.microsoft.com/yumrepos/edge/
+enabled=1
+gpgcheck=1
+gpgkey=https://packages.microsoft.com/keys/microsoft.asc
+includepkgs=microsoft-edge-stable

images/shared/workstation.yaml

@@ -0,0 +1,56 @@
+# Minimal GNOME workstation, shared by the fedora-intune images. Include it
+# from a manifest that sets `opt-usrlocal: root` (finalize.d/60-opt-links).
+
+packages:
+  # Fedora integration normally provided by the upstream fedora.yaml (which we
+  # opt out of to avoid the Firefox RPM).
+  - fedora-release
+  - fedora-release-ostree-desktop
+  - fedora-flathub-remote
+
+  # GNOME desktop: gdm pulls gnome-session, gnome-settings-daemon,
+  # accountsservice, dconf and gnome-keyring-pam. gnome-initial-setup creates
+  # the first local user on first boot.
+  - gdm
+  - gnome-shell
+  - gnome-control-center
+  - gnome-initial-setup
+  - nautilus
+  - ptyxis
+  - pipewire
+  - pipewire-pulseaudio
+  - wireplumber
+  - xdg-desktop-portal-gnome
+  - xdg-user-dirs-gtk
+  - flatpak
+
+  # Session infrastructure base-atomic lacks with recommends off; see
+  # fedora-remote/custom.yaml.
+  - dbus-daemon
+  - systemd-pam
+  - mesa-dri-drivers
+  - mesa-libEGL
+
+  # The upstream initramfs config adds dracut's tpm2-tss module, which needs the
+  # tpm2 binary. fedora-remote gets it through Kanidm; list it explicitly here.
+  - tpm2-tools
+
+  # Proxmox guest integration (agent, console clipboard and resizing).
+  - qemu-guest-agent
+  - spice-vdagent
+
+# Microsoft Edge is the browser (Conditional Access needs it).
+exclude-packages:
+  - firefox
+
+add-files:
+  - ["50-workstation.preset", "/usr/lib/systemd/system-preset/50-workstation.preset"]
+  # Key-only SSH for local accounts.
+  - ["10-workstation-sshd.conf", "/etc/ssh/sshd_config.d/10-workstation-sshd.conf"]
+
+postprocess:
+  # uresourced breaks the GDM greeter's user manager; see fedora-remote.
+  - |
+    #!/usr/bin/env bash
+    set -xeuo pipefail
+    ln -sf /dev/null /etc/systemd/system/uresourced.service