[feat] extend database schema with new tables and indexes

database/main/armor.sql

@@ -0,0 +1,13 @@
+create table armor
+(
+    id              INTEGER
+        primary key,
+    item_id         INTEGER not null
+        unique
+        references item
+            on delete cascade,
+    ruestungsschutz INTEGER not null,
+    behaelinderung  REAL    not null,
+    zonen           TEXT
+);
+