This migrates the Newsfeed module to use the centralized HTTPFetcher
class (introduced in #4016), following the same pattern as the Calendar
module.
This continues the refactoring effort to centralize HTTP error handling
across all modules.
## Changes
**NewsfeedFetcher:**
- Refactored from function constructor to ES6 class (like the calendar
module in #3959)
- Replaced manual fetch() + timer handling with HTTPFetcher composition
- Uses structured error objects with translation keys
- Inherits smart retry strategies (401/403, 429, 5xx backoff)
- Inherits timeout handling (30s) and AbortController
**node_helper.js:**
- Updated error handler to use `errorInfo.translationKey`
- Simplified property access (`fetcher.url`, `fetcher.items`)
**Cleanup:**
- Removed `js/module_functions.js` (`scheduleTimer` no longer needed)
- Removed `#module_functions` import from package.json
## Related
Part of the HTTPFetcher migration effort started in #4016.
Next candidate: Weather module (client-side → server-side migration).
Since the project's inception, I've missed a clear separation between
default and third-party modules.
This increases complexity within the project (exclude `modules`, but not
`modules/default`), but the mixed use is particularly problematic in
Docker setups.
Therefore, with this pull request, I'm moving the default modules to a
different directory.
~~I've chosen `default/modules`, but I'm not bothered about it;
`defaultmodules` or something similar would work just as well.~~
Changed to `defaultmodules`.
Let me know if there's a majority in favor of this change.
Kristjan ESPERANTO
Karsten Hassel