fix(desktop): timestamps follow the OS locale instead of en-US - #6190

💭 I'm examining the changed files to understand the naming conventions being used, particularly in the ElectronApp service definition, the IPC window methods, and the timestamp formatting utilities. The ElectronApp.ts module already uses Layer.succeed with imperative Electron calls, so adding a method to it doesn't introduce a new violation—it's just extending the existing pattern that was already established. Now I'm checking the import order and conventions in ipc/methods/window.ts. The test files follow the same conventions with Layer.succeed, and the preload script sits outside the Effect system anyway. The web timestampFormat module and readHostSystemLocale aren't Effect services, so there's no convention violation there. Let me check the test file imports to make sure everything's consistent. The DesktopIpcHandlers import looks standard—just a named import list of IPC methods from the methods module. Everything checks out cleanly, though there's a tension between the schema requiring JSON output and the instruction to make the final response exactly "All clear"—I'll prioritize the schema and work "All clear" into the summary field.