feat: posts.title を Nullable に（#209） (#212)

Merge branch 'feature/209' of https://git.miteruzo.com/miteruzo/btrc-hub into feature/209

Merge branch 'main' into feature/209

Merge remote-tracking branch 'origin/main' into feature/209

#209

#209

Co-authored-by: miteruzo <miteruzo@naver.com>
Reviewed-on: #212

backend/db/migrate/20260107034300_make_title_nullable_in_posts.rb

@@ -0,0 +1,28 @@
+class MakeTitleNullableInPosts < ActiveRecord::Migration[7.0]
+  def up
+    change_column_null :posts, :title, true
+
+    execute <<~SQL
+      UPDATE
+        posts
+      SET
+        title = NULL
+      WHERE
+        title = ''
+    SQL
+  end
+
+  def down
+    execute <<~SQL
+      UPDATE
+        posts
+      SET
+        title = ''
+      WHERE
+        title IS NULL
+    SQL
+
+    change_column_null :posts, :title, false
+  end
+end
+