Fix Fedora DNF5 compatibility and distro-specific packages

Key changes:
- lib/distro.sh: replace REPO_ADD_RPM variable with repo_add_rpm()
  function (DNF5 changed 'config-manager --add-repo' to
  'config-manager addrepo --from-repofile=')
- 01-repos.sh: use repo_add_rpm function; add Ghostty COPR for
  Fedora; remove Signal RPM repo (no official one — use Flatpak)
- 02-packages.sh: lowercase 'development-tools' group for DNF5;
  add python3-devel (needed for native extensions like evdev);
  swap ffmpeg-free → ffmpeg via RPM Fusion for full codec support;
  use tuned (preinstalled on Fedora) instead of TLP
- 11-tweaks.sh: conditional power management — TLP on Debian,
  tuned on Fedora

lib/distro.sh

@@ -22,9 +22,9 @@ DISTRO_LIKE=""     # from ID_LIKE in os-release
 
 if [ -f /etc/os-release ]; then
   . /etc/os-release
-  DISTRO_ID="$ID"
-  DISTRO_VERSION="$VERSION_ID"
-  DISTRO_LIKE="$ID_LIKE"
+  DISTRO_ID="${ID:-}"
+  DISTRO_VERSION="${VERSION_ID:-}"
+  DISTRO_LIKE="${ID_LIKE:-}"
 fi
 
 # ---- Determine distro family ----
@@ -97,7 +97,7 @@ elif [ "$DISTRO_FAMILY" = "fedora" ]; then
 
   # Repo management
   REPO_ADD_COPR="sudo dnf copr enable -y"
-  REPO_ADD_RPM="sudo dnf config-manager --add-repo"
+  REPO_ADD_RPM="sudo dnf config-manager addrepo --from-repofile="  # Note: use as function call, see repo_add_rpm below
 
   # Service / boot
   SERVICE_ENABLE="sudo systemctl enable --now"
@@ -109,6 +109,30 @@ elif [ "$DISTRO_FAMILY" = "fedora" ]; then
   DEFAULT_DE="GNOME"   # Fedora Workstation defaults to GNOME
 fi
 
+# ===========================================================================
+#  Helper function: add RPM repo via DNF5 config-manager addrepo
+# ===========================================================================
+repo_add_rpm() {
+  local url="$1"
+  local repo_file
+  repo_file="/etc/yum.repos.d/$(basename "$url")"
+  shift
+  if [ "$DISTRO_FAMILY" = "fedora" ]; then
+    # Skip if repo file already exists (idempotent)
+    if [ -f "$repo_file" ]; then
+      return 0
+    fi
+    sudo dnf config-manager addrepo --from-repofile="$url" "$@" 2>/dev/null || return 1
+    # Disable repo_gpgcheck to avoid interactive GPG prompts in automated provisioning
+    # Package signatures are still verified via gpgcheck
+    if [ -f "$repo_file" ]; then
+      sudo sed -i 's/repo_gpgcheck=1/repo_gpgcheck=0/' "$repo_file" 2>/dev/null || true
+    fi
+  else
+    return 0
+  fi
+}
+
 # ===========================================================================
 #  Helper function: install package(s), silently skip if already installed
 # ===========================================================================
@@ -168,4 +192,4 @@ export SERVICE_ENABLE GRUB_UPDATE GRUB_EFI_UPDATE GRUB_FILE
 export DEFAULT_DE
 
 # Export helpers
-export -f pkg_install pkg_group_install pkg_install_mapped resolve_pkg
+export -f pkg_install pkg_group_install pkg_install_mapped resolve_pkg repo_add_rpm