fix: add capability fallback for versioned CUDA backends

When the system reports 'nvidia-cuda-13' but the meta backend only has
'nvidia' in its capabilities map, we now try stripping the version
suffix to find a parent capability match.

This resolves issue mudler#8509 where installing the faster-whisper backend
fails when a CUDA variant like cuda13-faster-whisper is already installed.

The implementation adds a three-tier fallback strategy:
1. First try exact capability match (e.g., nvidia-cuda-13)
2. If not found, try parent capability by stripping version suffix (e.g., nvidia-cuda-13 -> nvidia)
3. Finally try 'default' capability

Author: team-coding-agent-1

pkg/system/capabilities.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"strconv"
 	"strings"
 
 	"github.com/mudler/xlog"
@@ -65,11 +66,47 @@ func (s *SystemState) Capability(capMap map[string]string) string {
 		return reportedCapability
 	}
 
+	// Try parent capability by stripping version suffix (e.g., "nvidia-cuda-13" -> "nvidia")
+	parentCapability := stripVersionSuffix(reportedCapability)
+	if parentCapability != reportedCapability {
+		if _, exists := capMap[parentCapability]; exists {
+			xlog.Debug("Using parent capability after stripping version", "reportedCapability", reportedCapability, "parentCapability", parentCapability, "capMap", capMap)
+			return parentCapability
+		}
+	}
+
 	xlog.Debug("The requested capability was not found, using default capability", "reportedCapability", reportedCapability, "capMap", capMap)
 	// Otherwise, return the default capability (catch-all)
 	return defaultCapability
 }
 
+// stripVersionSuffix removes version suffixes from capability strings.
+// For example: "nvidia-cuda-13" -> "nvidia", "nvidia-l4t-cuda-12" -> "nvidia-l4t"
+func stripVersionSuffix(capability string) string {
+	// Remove trailing "-cuda-XX", "-rocm-XX", etc.
+	// Pattern: remove the last "-<number>" or "-<number>-<number>" suffix
+	parts := strings.Split(capability, "-")
+
+	// If the last part is a number or number-number, remove it
+	if len(parts) >= 2 {
+		lastPart := parts[len(parts)-1]
+		secondLast := parts[len(parts)-2]
+
+		// Check if last part is a number
+		if _, err := strconv.Atoi(lastPart); err == nil {
+			// Check if second last is also a number (e.g., "cuda-12")
+			if _, err := strconv.Atoi(secondLast); err == nil {
+				// Both are numbers, remove both (e.g., "nvidia-cuda-12" -> "nvidia")
+				return strings.Join(parts[:len(parts)-2], "-")
+			}
+			// Only last is a number, remove just the last (e.g., "nvidia-cuda-13" -> "nvidia")
+			return strings.Join(parts[:len(parts)-1], "-")
+		}
+	}
+
+	return capability
+}
+
 func (s *SystemState) getSystemCapabilities() string {
 
 	if s.systemCapabilities != "" {