feat(ci): Add Fedora RPM package build workflow

Building on the Fedora packaging files from #950, this adds a CI workflow
to automatically build RPM packages for Fedora distributions.

The workflow:
- Builds both binary and debug RPMs using rpkg
- Tests package installation in the CI environment
- Publishes packages to Forgejo's RPM registry
- Uploads artifacts for easy download

Thanks to ginger for providing the initial Fedora build files that made
this CI pipeline possible.

docs/deploying/fedora.md

@@ -0,0 +1,189 @@
+# RPM Installation Guide
+
+Continuwuity is available as RPM packages for Fedora, RHEL, and compatible distributions.
+
+## Quick install (stable)
+
+For the latest stable version from release tags:
+
+```bash
+# Add the Continuwuity repository
+sudo dnf config-manager --add-repo https://forgejo.ellis.link/api/packages/continuwuation/rpm/stable/continuwuation.repo
+
+# Install Continuwuity
+sudo dnf install continuwuity
+
+# Enable automatic updates (optional)
+sudo dnf install dnf-automatic
+sudo systemctl enable --now dnf-automatic.timer
+```
+
+## Development builds
+
+For development builds from the main branch:
+
+```bash
+# Add the dev repository
+sudo dnf config-manager --add-repo https://forgejo.ellis.link/api/packages/continuwuation/rpm/dev/continuwuation.repo
+
+# Install Continuwuity
+sudo dnf install continuwuity
+```
+
+## Feature branch builds
+
+Feature branches are published to their own groups. For example, for branch `tom/new-feature`:
+
+```bash
+# Add the branch-specific repository (replace branch name)
+sudo dnf config-manager --add-repo https://forgejo.ellis.link/api/packages/continuwuation/rpm/tom-new-feature/continuwuation.repo
+
+# Install Continuwuity
+sudo dnf install continuwuity
+```
+
+Note: Branch names are sanitized (slashes become hyphens, lowercase only).
+
+## Direct package installation
+
+To install a specific version without adding the repository:
+
+```bash
+# Latest stable release
+sudo dnf install https://forgejo.ellis.link/api/packages/continuwuation/rpm/stable/continuwuity
+
+# Latest development build (main branch)
+sudo dnf install https://forgejo.ellis.link/api/packages/continuwuation/rpm/dev/continuwuity
+
+# Specific feature branch (replace branch-name)
+sudo dnf install https://forgejo.ellis.link/api/packages/continuwuation/rpm/branch-name/continuwuity
+```
+
+## Managing automatic updates
+
+### Option 1: DNF Automatic (recommended)
+
+```bash
+# Install dnf-automatic
+sudo dnf install dnf-automatic
+
+# Configure update policy
+sudo nano /etc/dnf/automatic.conf
+# Set: apply_updates = yes
+
+# Enable the service
+sudo systemctl enable --now dnf-automatic.timer
+```
+
+### Option 2: Manual updates
+
+```bash
+# Check for updates
+sudo dnf check-update continuwuity
+
+# Update to latest version
+sudo dnf update continuwuity
+```
+
+## Switching between channels
+
+```bash
+# List enabled repositories
+dnf repolist | grep continuwuation
+
+# Disable current repository (use actual repo name from above)
+sudo dnf config-manager --set-disabled continuwuation-stable
+# or
+sudo dnf config-manager --set-disabled continuwuation-dev
+# or for feature branches
+sudo dnf config-manager --set-disabled continuwuation-branch-name
+
+# Enable desired repository
+sudo dnf config-manager --set-enabled continuwuation-stable
+# or
+sudo dnf config-manager --set-enabled continuwuation-dev
+
+# Update to the new channel's version
+sudo dnf update continuwuity
+```
+
+## Verifying installation
+
+```bash
+# Check installed version
+rpm -q continuwuity
+
+# View package information
+rpm -qi continuwuity
+
+# List installed files
+rpm -ql continuwuity
+
+# Verify package integrity
+rpm -V continuwuity
+```
+
+## Systemd service management
+
+Continuwuity includes a systemd service file:
+
+```bash
+# Start the service
+sudo systemctl start conduwuit
+
+# Enable on boot
+sudo systemctl enable conduwuit
+
+# Check status
+sudo systemctl status conduwuit
+
+# View logs
+sudo journalctl -u conduwuit -f
+```
+
+## Uninstallation
+
+```bash
+# Stop and disable the service
+sudo systemctl stop conduwuit
+sudo systemctl disable conduwuit
+
+# Remove the package
+sudo dnf remove continuwuity
+
+# Remove the repository (optional)
+sudo rm /etc/yum.repos.d/continuwuation-*.repo
+```
+
+## Troubleshooting
+
+### GPG key issues
+
+If you encounter GPG key errors, you can temporarily disable GPG checking:
+
+```bash
+sudo dnf --nogpgcheck install continuwuity
+```
+
+### Repository metadata issues
+
+Clear and rebuild the cache:
+
+```bash
+sudo dnf clean all
+sudo dnf makecache
+```
+
+### Finding specific versions
+
+List all available versions:
+
+```bash
+dnf --showduplicates list continuwuity
+```
+
+Install a specific version:
+
+```bash
+sudo dnf install continuwuity-<version>
+```