style: drop redundant comments and apply formatting

Frontend now uses double quotes and semicolons. No behaviour change.

backend/schema.sql

@@ -19,8 +19,6 @@ CREATE TABLE IF NOT EXISTS genres (
     name TEXT NOT NULL UNIQUE
 );
 
--- WHERE NOT EXISTS instead of ON CONFLICT: ON CONFLICT consumes a sequence value per row
--- on every startup, which would eventually overflow SMALLSERIAL.
 INSERT INTO genres (name)
 SELECT seed.name
   FROM (VALUES ('Fiction'), ('Non-Fiction'), ('Mystery'), ('Thriller'), ('Science Fiction'),