fix: use tee to write repo file instead of dnf config-manager

dnf config-manager cannot read from /dev/stdin as a repo file source.
Write the repo file directly with tee instead.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

readme.md

@@ -126,10 +126,10 @@ sudo dnf install sequoia-sq
 
 ```bash
 sudo rpm --import https://rpm.lair.cafe/<short-id>.gpg
-sudo dnf config-manager addrepo --from-repofile=/dev/stdin <<EOF
-[lair-rpm]
-name=lair.cafe RPM repo
-baseurl=https://rpm.lair.cafe/fedora/43/x86_64
+sudo tee /etc/yum.repos.d/lair-cafe.repo > /dev/null <<'EOF'
+[lair-cafe]
+name=lair.cafe RPM Repository
+baseurl=https://rpm.lair.cafe/fedora/$releasever/$basearch/
 enabled=1
 gpgcheck=1
 gpgkey=https://rpm.lair.cafe/<short-id>.gpg