Rework text to blob in sqlite to support utf16

backend/ddl.sql

@@ -1,12 +1,12 @@
 create table guild (
 	id integer primary key,
-	name text
+	name blob
 );
 create unique index idx_guild_name on guild(name);
 
 create table player (
 	id integer primary key,
-	name text,
+	name blob,
 	guild integer references guild(id)
 );
 create unique index idx_player_name on player(name);
@@ -15,12 +15,12 @@ create table association (
 	id integer primary key,
 	lhs integer references player(id),
 	rhs integer references player(id),
-	note text
+	note blob
 );
 
 create table note (
 	id integer primary key,
-	content text,
+	content blob,
 	timestamp string,
 	player integer references player(id)
 );