most of a dash views api impl

crates/migrate/data/migrations/55.sql

@@ -0,0 +1,27 @@
+-- database version 55
+-- dashboard views
+
+create function generate_dash_view_id_inner() returns char(10) as $$
+    select string_agg(substr('aieu234567890', ceil(random() * 13)::integer, 1), '') from generate_series(1, 10)
+$$ language sql volatile;
+
+
+create function generate_dash_view_id() returns char(10) as $$
+declare newid char(10);
+begin
+    loop
+        newid := generate_dash_view_id_inner();
+        if not exists (select 1 from dash_views where id = newid) then return newid; end if;
+    end loop;
+end
+$$ language plpgsql volatile;
+
+create table dash_views (
+    id text not null primary key default generate_dash_view_id(),
+    system int references systems(id) on delete cascade,
+    name text not null,
+    value text not null,
+    unique (system, name)
+);
+
+update info set schema_version = 55;