fix: stabilize systemd deployment and release updates

deploy/install.sh

@@ -31,6 +31,7 @@ INSTALL_TRANSACTION_ARMED=false
 INSTALL_COMMITTED=false
 RELEASE_DIR=
 BACKUP_DIR=
+JAVA_BIN=
 JAVA_STAGED_DIR=
 JAVA_PREVIOUS_DIR=
 JAVA_ACTIVATED=false
@@ -81,6 +82,15 @@ preflight_host() {
   esac
   [ "$host_bits" = "$expected_bits" ] \
     || die "CPU architecture and userspace word size do not match: $HOST_ARCH/$host_bits-bit"
+  if [ "$HOST_ARCH" = x86 ]; then
+    getconf GNU_LIBC_VERSION >/dev/null 2>&1 \
+      || die "32-bit Linux deployment requires glibc; the downloaded i686 Java runtime is not compatible with musl"
+    if ! for loader in /lib/ld-linux.so.2 /lib32/ld-linux.so.2 /lib/i386-linux-gnu/ld-linux.so.2; do
+      [ -x "$loader" ] && break
+    done; then
+      die "32-bit Linux deployment requires the glibc loader /lib/ld-linux.so.2"
+    fi
+  fi
   [[ "$TRUSTED_PUBLIC_KEY_SHA256" =~ ^[0-9A-Fa-f]{64}$ ]] \
     || die "Set KAIDI_RELEASE_PUBLIC_KEY_SHA256 to the trusted release public-key SHA-256"
   case "$REINSTALL" in
@@ -209,6 +219,17 @@ install_packages() {
   fi
 }
 
+preflight_runtime_commands() {
+  local command_name
+  for command_name in \
+    awk bash chmod chown cp curl cut date find getconf getent grep gzip head id install jq journalctl \
+    ln mktemp mv nologin openssl readlink rm runuser sed sha256sum sleep sort systemctl \
+    systemd-analyze tar tr useradd usermod groupadd wc flock setsid; do
+    command -v "$command_name" >/dev/null 2>&1 \
+      || die "Required command is missing after dependency preparation: $command_name"
+  done
+}
+
 azul_arch() {
   case "${HOST_ARCH:-$(normalized_host_arch)}" in
     x86_64) printf x86 ;;
@@ -282,12 +303,13 @@ system_java_home() {
 
 prepare_java() {
   local api java_metadata package_metadata package_uuid java_url java_sha256 actual_sha256 system_home java_line
+  JAVA_BIN=
+  JAVA_STAGED_DIR=
   if system_home=$(system_java_home); then
-    JAVA_STAGED_DIR="$WORK_DIR/java.next"
-    mkdir -p "$JAVA_STAGED_DIR"
-    log "Copying existing Java 17 runtime from $system_home into the managed application directory"
-    COPYFILE_DISABLE=1 cp -R "$system_home/." "$JAVA_STAGED_DIR/"
-    java_line=$("$JAVA_STAGED_DIR/bin/java" -version 2>&1 | head -n 1)
+    JAVA_BIN="$system_home/bin/java"
+    java_line=$("$JAVA_BIN" -version 2>&1 | head -n 1) \
+      || die "The existing Java runtime cannot start on this host"
+    log "Using existing Java 17+ runtime at $system_home"
     log "Local Java verified: $java_line"
     return 0
   fi
@@ -312,11 +334,14 @@ prepare_java() {
   tar -xzf "$WORK_DIR/java.tar.gz" --strip-components=1 -C "$JAVA_STAGED_DIR"
   java_arch_matches_host "$JAVA_STAGED_DIR/bin/java" \
     || die "Downloaded Java runtime architecture does not match $HOST_ARCH"
-  java_line=$("$JAVA_STAGED_DIR/bin/java" -version 2>&1 | head -n 1)
+  java_line=$("$JAVA_STAGED_DIR/bin/java" -version 2>&1 | head -n 1) \
+    || die "The downloaded Java runtime cannot start; verify glibc and the host architecture"
+  JAVA_BIN="$APP_ROOT/runtime/java/bin/java"
   log "Downloaded Java verified: $java_line"
 }
 
 activate_java() {
+  [ -n "$JAVA_STAGED_DIR" ] || return 0
   mkdir -p "$APP_ROOT/runtime"
   JAVA_PREVIOUS_DIR="$WORK_DIR/java.previous"
   if [ -e "$APP_ROOT/runtime/java" ] || [ -L "$APP_ROOT/runtime/java" ]; then
@@ -383,10 +408,12 @@ verify_service_access() {
   runuser -u "$SERVICE_USER" -- sh -c \
     'cd "$1" && test -r app.jar && test -r public/index.html' sh "$APP_ROOT/current" \
     || die "$SERVICE_USER cannot traverse or read the active release"
-  runuser -u "$SERVICE_USER" -- test -x "$APP_ROOT/runtime/java/bin/java" \
-    || die "$SERVICE_USER cannot execute the managed Java runtime"
-  runuser -u "$SERVICE_USER" -- "$APP_ROOT/runtime/java/bin/java" -version >/dev/null 2>&1 \
-    || die "The managed Java runtime cannot execute as $SERVICE_USER"
+  [ -n "$JAVA_BIN" ] && [ -x "$JAVA_BIN" ] \
+    || die "The selected Java runtime is unavailable at $JAVA_BIN"
+  runuser -u "$SERVICE_USER" -- test -x "$JAVA_BIN" \
+    || die "$SERVICE_USER cannot execute the selected Java runtime"
+  runuser -u "$SERVICE_USER" -- "$JAVA_BIN" -version >/dev/null 2>&1 \
+    || die "The selected Java runtime cannot execute as $SERVICE_USER"
   runuser -u "$SERVICE_USER" -- test -w "$STATE_ROOT/files" \
     || die "$SERVICE_USER cannot write the file-storage directory"
   runuser -u "$SERVICE_USER" -- test -w "$UPDATE_STATE_ROOT/inbox" \
@@ -828,6 +855,7 @@ validate_inputs
 configure_app_port
 preflight_host
 install_packages
+preflight_runtime_commands
 
 BASE=${RELEASE_BASE_URL%/}
 WORK_DIR=$(mktemp -d)
@@ -926,6 +954,7 @@ if [ "$SETUP_WIZARD" = true ]; then
 fi
 write_env_file_preserving_unknown "$CONFIG_ROOT/kaidi.env" \
   SPRING_PROFILES_ACTIVE production \
+  KAIDI_JAVA_BIN "$JAVA_BIN" \
   SERVER_PORT "$APP_PORT" \
   SERVER_ADDRESS "$SERVER_ADDRESS" \
   SESSION_COOKIE_SECURE "$SESSION_COOKIE_SECURE" \
@@ -963,6 +992,7 @@ write_env_file "$CONFIG_ROOT/update.env" \
   KAIDI_APP_ROOT "$APP_ROOT" \
   KAIDI_UPDATE_STATE_ROOT "$UPDATE_STATE_ROOT" \
   KAIDI_SERVICE_NAME kaidi-finance.service \
+  KAIDI_JAVA_BIN "$JAVA_BIN" \
   KAIDI_HEALTH_URL "$HEALTH_URL" \
   KAIDI_APP_INDEX_URL "$APP_INDEX_URL" \
   KAIDI_DB_CONTAINER "${KAIDI_DB_CONTAINER:-}" \