chore(ai): establish single source of truth and cleanup legacy rules

.ai/scripts/build-prompts.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Nutze Junies robuste Pfad-Ermittlung
+source "$(dirname "${BASH_SOURCE[0]}")/lib/common.sh"
+REPO_ROOT="$(resolve_repo_root)"
+cd "$REPO_ROOT"
+
+AI_DIR=".ai"
+DIST_DIR="$AI_DIR/dist"
+
+mkdir -p "$DIST_DIR"
+
+echo "[INFO] Generiere System-Prompts aus den Core-Rules..."
+
+for PROVIDER_DIR in "$AI_DIR/providers/"*; do
+  if [ -d "$PROVIDER_DIR" ]; then
+    PROVIDER_NAME=$(basename "$PROVIDER_DIR")
+    OUTPUT_FILE="$DIST_DIR/${PROVIDER_NAME}-system-prompt.md"
+
+    echo "-> Baue Prompt für: $PROVIDER_NAME"
+
+    # 1. Basis-Identität schreiben
+    cat "$AI_DIR/prompts/system/base.md" > "$OUTPUT_FILE"
+    echo -e "\n\n" >> "$OUTPUT_FILE"
+
+    # 2. Alle globalen Regeln anhängen
+    for RULE_FILE in "$AI_DIR/rules/"*.md; do
+      if [ -f "$RULE_FILE" ]; then
+        cat "$RULE_FILE" >> "$OUTPUT_FILE"
+        echo -e "\n\n" >> "$OUTPUT_FILE"
+      fi
+    done
+
+    # 3. Provider-Spezifika anhängen
+    if [ -f "$PROVIDER_DIR/overlay.md" ]; then
+      cat "$PROVIDER_DIR/overlay.md" >> "$OUTPUT_FILE"
+    fi
+
+    echo "[OK] $OUTPUT_FILE erfolgreich erstellt."
+  fi
+done