refactor: Apply cache fixes directly to existing runner configs

- Update all runner configuration files with cache networking fixes:
  - config_docker.yaml
  - config_heavy.yaml
  - config_light.yaml
  - config_security.yaml
- Remove separate config_cache_fixed.yaml file
- Update troubleshooting scripts to use updated configs
- Update documentation to reference existing config files

All runner configs now have:
- Fixed cache host: host.docker.internal
- Fixed cache port: 44029
- Host networking for better container connectivity

This provides a cleaner approach by updating existing configs
instead of maintaining a separate fixed configuration file.

runners/fix-cache-issues.sh

@@ -87,12 +87,15 @@ restart_cache_service() {
     pkill -f "act_runner" || true
     sleep 2
     
-    # Start with fixed configuration
-    if [ -f "config_cache_fixed.yaml" ]; then
-        echo "✅ Using fixed configuration"
-        nohup ./act_runner daemon --config config_cache_fixed.yaml > runner.log 2>&1 &
+    # Start with updated configuration
+    if [ -f "config_docker.yaml" ]; then
+        echo "✅ Using updated Docker configuration"
+        nohup ./act_runner daemon --config config_docker.yaml > runner.log 2>&1 &
+    elif [ -f "config_heavy.yaml" ]; then
+        echo "✅ Using updated heavy configuration"
+        nohup ./act_runner daemon --config config_heavy.yaml > runner.log 2>&1 &
     else
-        echo "⚠️  Fixed configuration not found, using default"
+        echo "⚠️  Updated configuration not found, using default"
         nohup ./act_runner daemon > runner.log 2>&1 &
     fi