refactor(status-page): tighten the theme-fields backend after second review

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- Extract makeStatusPage from the two test files that duplicated it (test/unit/services/statusPageService.test.ts and test/unit/controllers/statusPageThemeFlag.test.ts) into test/helpers/makeStatusPage.ts. Both files now import the shared helper, matching the existing test/helpers/ convention used for repository fakes and provider contracts
- Add a blank line in statusPageController.getStatusPageByUrl between the normalizedMonitors map and the themesEnabled lookup so the response-shaping section breathes a bit
- Drop the obsolete localStorage references from the plan doc that survived from an earlier draft of the design — the public page never persisted a per-visitor mode choice in localStorage, so the test bullet under 2.11 and the risk row both pointed at functionality that does not exist

server/src/controllers/statusPageController.ts

@@ -130,6 +130,7 @@ class StatusPageController implements IStatusPageController {
 				}
 				return { ...monitor, checks: normalizedChecks };
 			});
+
 			const themesEnabled = this.settingsService.areStatusPageThemesEnabled();
 			return res.status(200).json({
 				success: true,