status(host): configure external status page and uptime monitoring host

resources/external/status/docker_compose/config/general.yaml

@@ -0,0 +1,25 @@
+storage:
+  type: postgres
+  path: "postgres://${POSTGRES_USER}:${POSTGRES_PASSWORD}@database:5432/${POSTGRES_DB}?sslmode=disable"
+
+ui:
+  title: CCCHH Status
+  description: Automated uptime monitoring and status page for CCCHH services. Powered by Gatus.
+  header: CCCHH Status
+  buttons:
+    - name: Website
+      link: "https://hamburg.ccc.de"
+    - name: Git
+      link: "https://git.hamburg.ccc.de"
+    - name: Kontakt & Impressum
+      link: "https://hamburg.ccc.de/imprint/"
+  default-sort-by: group
+
+alerting:
+  matrix:
+    server-url: "https://matrix-client.matrix.org"
+    access-token: "${MATRIX_ACCESS_TOKEN}"
+    internal-room-id: "!jG755onbGAH-lZsZo8SRKtlsncSMvq7nzPhwCi5CgdQ"
+
+# A bit more than the default 5 concurrent checks should be fine.
+concurrency: 15