feat(scripts): add CI utilities for versioning and changelog

- Add scripts to detect version changes and generate changelogs
- Include setup for installing and configuring git-cliff
- Automate release creation and changelog updates for CI workflows
- Improve Git author setup for consistent commits

scripts/install-git-cliff.sh

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+# install-git-cliff.sh – holt neueste oder gewünschte git-cliff-Binary (x86_64)
+# Usage: sudo ./install-git-cliff.sh        # neueste Version
+#        sudo ./install-git-cliff.sh 2.9.0  # bestimmte Version
+set -euo pipefail
+
+REPO="orhun/git-cliff"
+ARCH_OS="x86_64-unknown-linux-gnu"
+INSTALL_DIR="/usr/local/bin"
+VERSION="${1:-latest}"
+
+need() { command -v "$1" >/dev/null || { echo "$1 fehlt"; exit 1; }; }
+need curl; need tar; need grep; need sed; need awk
+
+# 1 Version ermitteln → Release-JSON abrufen
+if [[ "$VERSION" == "latest" ]]; then
+  API_URL="https://api.github.com/repos/${REPO}/releases/latest"
+else
+  API_URL="https://api.github.com/repos/${REPO}/releases/tags/v${VERSION}"
+fi
+
+echo "🔍 Hole Release-Info ($API_URL)…"
+JSON=$(curl -sL "$API_URL")
+
+VERSION=$(echo "$JSON" | grep -m1 '"tag_name":' | sed -E 's/.*"v?([^"]+)".*/\1/')
+ASSET_URL=$(echo "$JSON" |
+  grep -Eo '"browser_download_url": *"[^"]+' |
+  cut -d'"' -f4 |
+  grep "${ARCH_OS}\\.tar" | head -n1)
+
+[[ -z "$ASSET_URL" ]] && { echo "❌ passender Asset nicht gefunden"; exit 1; }
+
+ASSET_FILE=$(basename "$ASSET_URL")
+echo "📦 Lade git-cliff v${VERSION} (${ASSET_FILE}) …"
+TMP=$(mktemp -d)
+curl -#L -o "${TMP}/${ASSET_FILE}" "$ASSET_URL"
+
+# 2 Entpacken je nach Endung
+case "$ASSET_FILE" in
+  *.tar.gz|*.tgz) tar -C "$TMP" -xzf "${TMP}/${ASSET_FILE}" ;;
+  *.tar.xz)       tar -C "$TMP" -xJf "${TMP}/${ASSET_FILE}" ;;
+  *.zip)          need unzip; unzip -q "${TMP}/${ASSET_FILE}" -d "$TMP" ;;
+  *) echo "❌ Unbekanntes Archivformat: $ASSET_FILE"; exit 1 ;;
+esac
+
+BIN_PATH=$(find "$TMP" -type f -name git-cliff -perm -u+x | head -n1)
+[[ -z "$BIN_PATH" ]] && { echo "❌ Binary nicht gefunden"; exit 1; }
+
+sudo install -m755 "$BIN_PATH" "${INSTALL_DIR}/git-cliff"
+echo "✅ git-cliff $(git-cliff --version) installiert unter ${INSTALL_DIR}"