fedora-cosmic: add OBS network:idm repo for Kanidm packages

Kanidm is not in the Fedora repos; it ships from the openSUSE OBS
network:idm project. Add per-distro repo files (Fedora_44 / Fedora_Rawhide)
and teach build.sh to overlay repos/<distro>/*.repo.

build.sh

@@ -137,6 +137,9 @@ case "${BUILD_MODE}" in
     if compgen -G "${IMAGE_DIR}/repos/*.repo" >/dev/null; then
       cp "${IMAGE_DIR}"/repos/*.repo "${BUILD_DIR}/upstream/"
     fi
+    if compgen -G "${IMAGE_DIR}/repos/${DISTRO}/*.repo" >/dev/null; then
+      cp "${IMAGE_DIR}"/repos/"${DISTRO}"/*.repo "${BUILD_DIR}/upstream/"
+    fi
     if [[ -d "${IMAGE_DIR}/files" ]]; then
       cp -a "${IMAGE_DIR}/files/." "${BUILD_DIR}/upstream/"
     fi
@@ -165,6 +168,9 @@ case "${BUILD_MODE}" in
     if compgen -G "${local_dir}/repos/*.repo" >/dev/null; then
       cp "${local_dir}"/repos/*.repo "${local_dir}/"
     fi
+    if compgen -G "${local_dir}/repos/${DISTRO}/*.repo" >/dev/null; then
+      cp "${local_dir}"/repos/"${DISTRO}"/*.repo "${local_dir}/"
+    fi
 
     if [[ "${TOKEN2}" == "1" ]]; then
       setup_token2_repo "${local_dir}"