build(release): several apps released in one run (train:minor learn), their version commits pushed without the checks

The release tool and tool/with_signing_keys.sh take several apps, each with its version
after a colon or none, and release them one after another, each as alone, stopping at
the first that fails; the key script fetches every named app's key.

The pre-push hook skips tool/check.dart when a push brings release commits alone: the
release tool's chore(release) subject, an app's pubspec changed in its version line and
its texts of what's new, nothing else (tool/release_push.dart). Signatures are checked as
before, and CI still runs the checks. A release no longer costs a run of the checks.

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

tool/with_signing_keys.sh

@@ -10,6 +10,7 @@
 #
 #   tool/with_signing_keys.sh <app> [release.dart's arguments]
 #   tool/with_signing_keys.sh train minor --dry-run
+#   tool/with_signing_keys.sh train:minor learn          several, one after another
 #   tool/with_signing_keys.sh fdroid [tool/fdroid_repo.sh's arguments]
 #
 # The last runs tool/fdroid_repo.sh alone, with the F-Droid index's key and its password
@@ -29,19 +30,34 @@ fail() {
   exit 1
 }
 
-[ $# -ge 1 ] || fail 'Usage: tool/with_signing_keys.sh <app | fdroid> [arguments]'
-app="$1"
-shift
+[ $# -ge 1 ] || fail 'Usage: tool/with_signing_keys.sh <app[:version] … | fdroid> [arguments]'
 
 # Each app released (tool/src/release/apps.dart): the variable its keystore's path goes
-# in (its AndroidSigning's keystoreVariable) and the item keeping it.
-case "$app" in
-  fdroid) ;;
+# in (its AndroidSigning's keystoreVariable) and the item keeping it, set for the app $1.
+key_of() {
+  case "$1" in
   learn) app_variable=HALKYON_ANDROID_KEYSTORE app_item='Halkyon Learn – Android release keystore' ;;
   train) app_variable=HALKYON_TRAIN_ANDROID_KEYSTORE app_item='Halkyon Train – Android release keystore' ;;
   todo) app_variable=HALKYON_TODO_ANDROID_KEYSTORE app_item='Halkyon Todo – Android release keystore' ;;
-  *) fail "No signing key known for $app." ;;
-esac
+  *) fail "No signing key known for $1." ;;
+  esac
+}
+
+# The apps the arguments name (`train:minor learn`, `train minor --dry-run`): every
+# word but the options and a version on its own, without a version after a colon.
+apps=()
+if [ "$1" != fdroid ]; then
+  for word in "$@"; do
+    case "$word" in
+    -* | major | minor | patch) ;;
+    *) apps+=("${word%%:*}") ;;
+    esac
+  done
+  [ ${#apps[@]} -ge 1 ] || fail 'No app named.'
+  for app in "${apps[@]}"; do
+    key_of "$app"
+  done
+fi
 # The F-Droid repository's index key, the same for every app listed there.
 readonly fdroid_item='Halkyon Learn – F-Droid index keystore'
 # The Forgejo token releases publish with (write:repository), a login's password in
@@ -95,7 +111,8 @@ forgejo_token() {
   printf '%s' "$value"
 }
 
-if [ "$app" = fdroid ]; then
+if [ "$1" = fdroid ]; then
+  shift
   echo "▸ Fetching the F-Droid index's key from $vault"
   fetch "$fdroid_item" fdroid-index.p12 "$keys/fdroid-index.p12"
   export HALKYON_FDROID_KEYSTORE="$keys/fdroid-index.p12"
@@ -107,25 +124,32 @@ if [ "$app" = fdroid ]; then
   exit "$status"
 fi
 
-echo "▸ Fetching the signing keys from $vault"
-fetch "$app_item" android-release.p12 "$keys/android-release.p12"
-fetch "$fdroid_item" fdroid-index.p12 "$keys/fdroid-index.p12"
-
-export "$app_variable=$keys/android-release.p12"
-export HALKYON_FDROID_KEYSTORE="$keys/fdroid-index.p12"
 dry_run=false
 for argument in "$@"; do
   [ "$argument" = --dry-run ] && dry_run=true
 done
+
+echo "▸ Fetching the signing keys from $vault"
+# Each app's keystore under a name of its own, as each has a variable of its own.
+for app in "${apps[@]}"; do
+  key_of "$app"
+  fetch "$app_item" android-release.p12 "$keys/$app-android-release.p12"
+  export "$app_variable=$keys/$app-android-release.p12"
+  if ! $dry_run; then
+    app_password=$(password "$app_item")
+    export "${app_variable}_PASSWORD=$app_password"
+    unset app_password
+  fi
+done
+fetch "$fdroid_item" fdroid-index.p12 "$keys/fdroid-index.p12"
+export HALKYON_FDROID_KEYSTORE="$keys/fdroid-index.p12"
 if ! $dry_run; then
-  app_password=$(password "$app_item")
   fdroid_password=$(password "$fdroid_item")
-  export "${app_variable}_PASSWORD=$app_password"
   export HALKYON_FDROID_KEYSTORE_PASSWORD="$fdroid_password"
   token=$(forgejo_token)
   export HALKYON_FORGEJO_TOKEN="$token"
-  unset app_password fdroid_password token
+  unset fdroid_password token
 fi
 status=0
-dart run tool/release.dart "$app" "$@" || status=$?
+dart run tool/release.dart "$@" || status=$?
 exit "$status"