Implement Local Configuration Architecture and UI Improvements

This issue tracks the transition from the dual-build (prod/dev) system to a runtime local configuration file architecture.

### Tasks
- [ ] Store configuration locally (`config.json`) in the OS AppData directory.
- [ ] Remove all URL configuration and Dev/Prod flavor logic from the frontend UI.
- [ ] Unify Wazuh and NetBird under a single 'Enrollment' page/dropdown in the sidebar navigation.
- [ ] Mark 'Trivy' as 'Upcoming' on the Setup page and disable its installation for now.
- [ ] Make the NetBird checkbox checked by default on the Setup page.
- [ ] Hide Suricata configuration from the Setup page since it installs in IPS mode by default.
- [ ] Delete `*-dev` installation scripts and remove the GitHub Actions dual-build matrix.

Start by locating the frontend Setup page, sidebar navigation, installation scripts, and GitHub Actions workflow. Trace where configuration and Dev/Prod flavor logic are currently handled, then compare each listed task against those entry points. Done means local config is used, the UI reflects the requested enrollment and installation states, and the dual-build scripts and matrix are removed.

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