new: changes to enable daily-dangerous image builds

daily-dangerous image builds are standard desktop images for the devel
series, except all of the snaps are set to their respective edge
channels, and the dangerous model is used, hence its inclusion in this
commit.

Goes hand in hand with this MP:
https://code.launchpad.net/~andersson123/ubuntu-cdimage/+git/ubuntu-cdimage/+merge/490708

live-build/functions

@@ -566,11 +566,9 @@ _snap_post_process() {
             # If the 'core' snap is not present, assume we are coreXX-only and
             # install the snapd snap.
             channel=stable
-            # FIXME: This can be commented and uncommented to enable snaps from
-            # edge for development spikes.
-            # if [ $PROJECT = "ubuntu" ]; then
-            #     channel=edge
-            # fi
+            if [ $SUBPROJECT = "dangerous" ]; then
+                channel=$CHANNEL
+            fi
             if [ ! -f ${snaps_dir}/core_[0-9]*.snap ]; then
                 _snap_preseed $CHROOT_ROOT snapd "$channel"
             fi

live-build/ubuntu/hooks/030-ubuntu-live-system-seed.binary

@@ -41,6 +41,11 @@ model=/usr/share/livecd-rootfs/live-build/${PROJECT}/ubuntu-classic-amd64.model
 # see below note about "dangerous" model
 CHANNEL=${CHANNEL:-stable}
 
+# for the dangerous subproject, we need the dangerous model!
+if [ $SUBPROJECT = "dangerous" ]; then
+    model=/usr/share/livecd-rootfs/live-build/${PROJECT}/ubuntu-classic-amd64-dangerous.model
+fi
+
 channel=""
 if [ -n "${CHANNEL:-}" ]; then
     channel="--channel $CHANNEL"

live-build/ubuntu/ubuntu-classic-amd64-dangerous.model

@@ -0,0 +1,94 @@
+type: model
+authority-id: canonical
+series: 16
+brand-id: canonical
+model: ubuntu-classic-2510-amd64-dangerous
+architecture: amd64
+base: core24
+classic: true
+distribution: ubuntu
+grade: dangerous
+snaps:
+  -
+    default-channel: classic-25.10/edge
+    id: UqFziVZDHLSyO3TqSWgNBoAdHbLI4dAH
+    name: pc
+    type: gadget
+  -
+    default-channel: 25.10/beta
+    id: pYVQrBcKmBa0mZ4CCN7ExT6jH8rY1hza
+    name: pc-kernel
+    type: kernel
+  -
+    default-channel: latest/edge
+    id: amcUKQILKXHHTlmSa7NMdnXSx02dNeeT
+    name: core22
+    type: base
+  -
+    default-channel: latest/edge
+    id: dwTAh7MZZ01zyriOZErqd1JynQLiOGvM
+    name: core24
+    type: base
+  -
+    default-channel: latest/edge
+    id: PMrrV4ml8uWuEUDBT8dSGnKUYbevVhc4
+    name: snapd
+    type: snapd
+  -
+    default-channel: latest/edge
+    id: EISPgh06mRh1vordZY9OZ34QHdd7OrdR
+    name: bare
+    type: base
+  -
+    default-channel: 1/edge/ubuntu-25.10
+    id: EI0D1KHjP8XiwMZKqSjuh6W8zvcowUVP
+    name: firmware-updater
+    type: app
+  -
+    default-channel: 1/edge/ubuntu-25.10
+    id: FppXWunWzuRT2NUT9CwoBPNJNZBYOCk0
+    name: desktop-security-center
+    type: app
+  -
+    default-channel: 1/edge/ubuntu-25.10
+    id: aoc5lfC8aUd2VL8VpvynUJJhGXp5K6Dj
+    name: prompting-client
+    type: app
+  -
+    default-channel: 2/edge/ubuntu-25.10
+    id: gjf3IPXoRiipCu9K0kVu52f0H56fIksg
+    name: snap-store
+    type: app
+  -
+    default-channel: latest/edge/ubuntu-25.10
+    id: jZLfBRzf1cYlYysIjD2bwSzNtngY0qit
+    name: gtk-common-themes
+    type: app
+  -
+    default-channel: latest/edge/ubuntu-25.10
+    id: 3wdHCAVyZEmYsCMFDE9qt92UV8rC8Wdk
+    name: firefox
+    type: app
+  -
+    default-channel: latest/edge/ubuntu-25.10
+    id: lATO8HzwVvrAPrlZRAWpfyrJKlAJrZS3
+    name: gnome-42-2204
+    type: app
+  -
+    default-channel: latest/edge/ubuntu-25.10
+    id: IrwRHakqtzhFRHJOOPxKVPU0Kk7Erhcu
+    name: snapd-desktop-integration
+    type: app
+timestamp: 2025-05-01T12:00:00.0Z
+sign-key-sha3-384: 9tydnLa6MTJ-jaQTFUXEwHl1yRx7ZS4K5cyFDhYDcPzhS7uyEkDxdUjg9g08BtNn
+
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