manatee: Add schema

The household weekly plan at schema.ppp.pm: its module, certificate,
DNS record, backup and secrets. The link to puppy-tracker is prepared
but commented out until puppy-tracker with the integration feed is
deployed.

secrets/manatee/schema-invite-code.age

@@ -0,0 +1,7 @@
+age-encryption.org/v1
+-> ssh-ed25519 wkRvNA 73OdSBU5vi/uHFRBJRYCAaaMuT2xjv/k7Dk/lela3HQ
+SJFTTuaohubRB9tNtVGCJPlvQaeRfLUYnGl4oZWG/hI
+-> ssh-ed25519 +oNaHQ TWvVn/YL6dsUckjN/zkOA5Cgl63agqZSQi9j77GOhm4
+ay+p2r70U5++sG2KlOkqvo4ATKbSb+mZ14/y4XxeYaQ
+--- MhsKOuWdZL0xNU+ImVmQ+vRbvRK6Cgv8kjYr4Cby958
+#俸V
{ｧＮc3ﾈ錯pNWfﾃ汕�ﾉ/�ｧL頷ﾊﾔnｻ薰�ﾔｨ<#游ﾄ