사이트 설정 관리 추가

db/migrations/004_add_site_settings.sql

@@ -0,0 +1,28 @@
+CREATE TABLE IF NOT EXISTS site_settings (
+  id INTEGER PRIMARY KEY DEFAULT 1,
+  title TEXT NOT NULL DEFAULT 'sori.studio',
+  description TEXT NOT NULL DEFAULT 'sori.studio 개인 블로그',
+  site_url TEXT NOT NULL DEFAULT 'https://sori.studio',
+  logo_text TEXT NOT NULL DEFAULT '井',
+  copyright_text TEXT NOT NULL DEFAULT '©2026 sori.studio',
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+  CONSTRAINT site_settings_singleton_check CHECK (id = 1)
+);
+
+INSERT INTO site_settings (
+  id,
+  title,
+  description,
+  site_url,
+  logo_text,
+  copyright_text
+)
+VALUES (
+  1,
+  'sori.studio',
+  'sori.studio 개인 블로그',
+  'https://sori.studio',
+  '井',
+  '©2026 sori.studio'
+)
+ON CONFLICT (id) DO NOTHING;