packagecloud.io RPM repository is empty (0 packages across all distro variants)

### Description The packagecloud.io RPM repository at https://packagecloud.io/filips/FirefoxPWA appears to be completely empty — all distro variants have `packages="0"` in their `primary.xml`. This affects every variant checked: - `el/6/x86_64` - `fedora/40/x86_64` - `fedora/41/x86_64` - `fedora/42/x86_64` - `fedora/43/x86_64` Verification: ``` $ curl -sL "https://packagecloud.io/filips/FirefoxPWA/fedora/43/x86_64/repodata/primary.xml.gz" | gunzip <?xml version="1.0" encoding="UTF-8"?> <metadata xmlns="http://linux.duke.edu/metadata/common" xmlns:rpm="http://linux.duke.edu/metadata/rpm" packages="0"> <!--generated by the amazing packagecloud.io RPM indexer--> </metadata> ``` The repomd.xml timestamp for all variants is `1627840073` (August 2021), suggesting the repo hasn't been updated since then. ### Impact Users following the [installation instructions](https://packagecloud.io/filips/FirefoxPWA) to set up the DNF/rpm-ostree repo will get `Packages not found: firefoxpwa` even after successfully adding the repo. The only working install path for RPM-based systems is downloading directly from GitHub releases. ### Relation to Previous Issues This may be the root cause or a related issue to #645 and #711 (GPG signature failures), as those issues reference packages being found but with signature problems — which would require packages to actually exist in the repo. It's possible the repo was populated at some point and has since been cleared, or publishing to packagecloud was never fully set up for RPMs. ### Steps to Reproduce ```bash # Add the repo per instructions, then: sudo dnf install firefoxpwa # or rpm-ostree install firefoxpwa # Result: Packages not found: firefoxpwa ``` ### Suggested Fix Either: 1. Publish RPM packages to packagecloud.io as part of the release workflow, or 2. Update the installation documentation to point RPM users directly to GitHub releases instead The GitHub releases do contain working RPM packages (e.g., `firefoxpwa-2.18.2-1.x86_64.rpm`), so the binaries exist — they just aren't being pushed to packagecloud.