feat(quick-260406-j44): add idempotent dev seed runner and db:seed:dev script

- Seed runner inserts user, categories, global items, tags, user items,
  threads with candidates, setups, and settings in FK order
- Idempotent: checks for dev-user-seed logtoSub before running
- Reuses seedGlobalItems() for base catalog data
- Added db:seed:dev npm script to package.json

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

package.json

@@ -13,7 +13,8 @@
 		"test": "bun test tests/",
 		"test:e2e": "bunx playwright test",
 		"test:e2e:ui": "bunx playwright test --ui",
-		"lint": "bunx @biomejs/biome check ."
+		"lint": "bunx @biomejs/biome check .",
+		"db:seed:dev": "bun run src/db/dev-seed.ts"
 	},
 	"devDependencies": {
 		"@biomejs/biome": "^2.4.7",