feat: move network config to db

closes https://github.com/LNVPS/api/issues/16

lnvps_db/migrations/20250325113115_extend_ip_range.sql

@@ -0,0 +1,23 @@
+create table router
+(
+    id      integer unsigned not null auto_increment primary key,
+    name    varchar(100) not null,
+    enabled bit(1)       not null,
+    kind    smallint unsigned not null,
+    url     varchar(255) not null,
+    token   varchar(128) not null
+);
+create table access_policy
+(
+    id        integer unsigned not null auto_increment primary key,
+    name      varchar(100) not null,
+    kind      smallint unsigned not null,
+    router_id integer unsigned,
+    interface varchar(100),
+    constraint fk_access_policy_router foreign key (router_id) references router (id)
+);
+alter table ip_range
+    add column reverse_zone_id varchar(255),
+    add column access_policy_id integer unsigned;
+alter table ip_range
+    add constraint fk_ip_range_access_policy foreign key (access_policy_id) references access_policy (id);