Refactor CI/CD pipeline and Dockerfile structure; remove obsolete build.yml and multi-stage Dockerfile, add default configuration for monitoring

default_config.hcl

@@ -0,0 +1,28 @@
+check_interval = "1s"
+
+monitor "mdstat_raid" {
+  command = [
+    "sh",
+    "-c",
+    "grep -q '\\[U_\\|_U\\]' /host_proc/mdstat && exit 1 || exit 0"
+  ]
+  check_interval = "30s"
+  alert_after = 1
+
+  alert_down = ["email_alert"]
+  alert_up   = ["email_recovery"]
+}
+alert "email_alert" {
+  command = [
+      "sh",
+          "-c",
+            "EMAIL=$EMAIL_RECIPIENT; printf 'Subject: RAID ALERT\nTo: %s\n\nRAID degraded\n' \"$EMAIL\" | sendmail -t || true"
+                ]
+}
+alert "email_recovery" {
+  command = [
+      "sh",
+          "-c",
+              "EMAIL=$EMAIL_RECIPIENT; printf 'Subject: RAID ALERT\nTo: %s\n\nRAID clean\n' \"$EMAIL\" | sendmail -t || true"
+                ]
+}