build(todo): Todo deployable beside Learn's server, and released as an APK, on F-Droid and as a snap (ADR 0033, step 5)

deploy/compose.todo.yaml adds Todo's server at todo.halkyon.eu, a member
of Learn's register, its database halkyon_todo in the instance's
PostgreSQL, its image built as Train's. redeploy.sh and backup.sh go over
every app server .env switches on (train, todo). Each compose file names
its server to the register in a variable of its own
(INSTANCE_MEMBER_TRAIN, INSTANCE_MEMBER_TODO), which halkyon_base adds to
INSTANCE_MEMBERS, each address once, as a second compose file's default
would have replaced Train's.

apps/todo/release.dart configures the release tool for Todo's APK and
snap: a key of its own (pinned once made; until then nothing is
released), the F-Droid listing (Time, NonFreeNet), and the snap from
apps/todo/snap/, which the tool builds in a clone of the repository at the
tag with that folder in place of snap/, as snapcraft builds one recipe a
folder and the root's is Learn's. What's new for 0.1.0 in English and
German, now shown. Android's backup and transfer are off, as Train's
(D53): the reminders scheduled keep their tasks' titles unsealed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

deploy/backup.sh

@@ -4,8 +4,9 @@
 # how it was set up and how to restore.
 #
 # Everything people keep is in the database, their files too (Serverpod's database
-# cloud storage), and in Train's where .env switches Train on (compose.train.yaml,
-# Halkyon Train's ADR 0030, D46), but for the releases of published studysets, which are git
+# cloud storage), and in Train's and Todo's where .env switches each on (compose.train.yaml,
+# Halkyon Train's ADR 0030, D46; compose.todo.yaml, Halkyon Todo's ADR 0033), but for the
+# releases of published studysets, which are git
 # repositories in the server's volume: a dump and a bundle of each repository cover
 # the instance; the secrets in deploy/.env are kept in Proton Pass instead. restic stores the dump encrypted in a Hetzner Storage Box
 # and keeps 24 hourly, 7 daily, 4 weekly and 3 monthly snapshots (decided 2026-10-03).
@@ -36,11 +37,15 @@ cd "$(dirname "$0")"
 # the last hour and stores it only once; restic compresses what it stores.
 mkdir -p -m 700 "$HOME/backups"
 dump="$HOME/backups/latest.dump"
-train_dump="$HOME/backups/latest-train.dump"
-train=
-if docker compose config --services | grep -qx train-server; then
-  train=yes
-fi
+# The apps' servers .env switches on beside Learn's, each with its database
+# (halkyon_<app>) dumped to latest-<app>.dump.
+services=$(docker compose config --services)
+apps=
+for app in train todo; do
+  if printf '%s\n' "$services" | grep -qx "$app-server"; then
+    apps="$apps $app"
+  fi
+done
 (
   umask 077
   # Never during a deploy (redeploy.sh holds this lock): its migrations would wait
@@ -48,14 +53,17 @@ fi
   exec 9>"$HOME/.redeploy.lock"
   flock 9
   docker compose exec -T postgres pg_dump -U halkyon_learn -Fc -Z 0 halkyon_learn >"$dump.partial"
-  if [ -n "$train" ]; then
-    docker compose exec -T postgres pg_dump -U halkyon_learn -Fc -Z 0 halkyon_train >"$train_dump.partial"
-  fi
+  for app in $apps; do
+    docker compose exec -T postgres pg_dump -U halkyon_learn -Fc -Z 0 "halkyon_$app" \
+      >"$HOME/backups/latest-$app.dump.partial"
+  done
 )
 mv "$dump.partial" "$dump"
-if [ -n "$train" ]; then
-  mv "$train_dump.partial" "$train_dump"
-fi
+set -- "$dump"
+for app in $apps; do
+  mv "$HOME/backups/latest-$app.dump.partial" "$HOME/backups/latest-$app.dump"
+  set -- "$@" "$HOME/backups/latest-$app.dump"
+done
 
 # Each repository as a git bundle, after the dump: a release the dump lacks is never
 # numbered again (the server numbers past the highest tag), while one the bundles
@@ -79,13 +87,9 @@ releases="$HOME/backups/repositories.tar"
 )
 mv "$releases.partial" "$releases"
 
-if [ -n "$train" ]; then
-  restic backup --quiet "$dump" "$train_dump" "$releases"
-else
-  restic backup --quiet "$dump" "$releases"
-fi
+restic backup --quiet "$@" "$releases"
 # By host alone: restic groups by the paths backed up too, so a path added (Train's
-# dump) would leave the snapshots before it a group of their own, never forgotten, and
+# dump, Todo's) would leave the snapshots before it a group of their own, never forgotten, and
 # a deleted account in them for good.
 restic forget --quiet --group-by host --keep-hourly 24 --keep-daily 7 --keep-weekly 4 --keep-monthly 3