refactor: simplify stack templates, move vars into group_vars/alpina

this vault setup for injective sensitive variables uses the approach described in https://docs.ansible.com/ansible/10/tips_tricks/ansible_tips_tricks.html#keep-vaulted-variables-safely-visible

roles/alpina/templates/services/monitoring/loki_config/loki-config.yaml.j2

@@ -0,0 +1,30 @@
+auth_enabled: false
+
+server:
+  http_listen_port: 3100
+
+common:
+  path_prefix: /loki
+  # TODO: Consider setting up S3 for storage
+  storage:
+    filesystem:
+      chunks_directory: /loki/chunks
+      rules_directory: /loki/rules
+  replication_factor: 1
+  ring:
+    kvstore:
+      store: inmemory
+
+schema_config:
+  configs:
+    - from: 2020-10-24
+      store: boltdb-shipper
+      object_store: filesystem
+      schema: v11
+      index:
+        prefix: index_
+        period: 24h
+
+# TODO: Figure this out
+ruler:
+  alertmanager_url: http://localhost:9093