PackageRecommendations: Add distribution to package recommendations

- Add required distribution field to RecommendPackageRequest
- Add modelVersion field to RecommendationsResponse
- Update frontend to send RHEL major version to API
- Add analytics tracking for distribution and modelVersion

Enables version-specific package recommendations and model usage tracking.

src/Components/CreateImageWizard/steps/Packages/PackageRecommendations.tsx

@@ -82,6 +82,7 @@ const PackageRecommendations = () => {
           recommendPackageRequest: {
             packages: packages.map((pkg) => pkg.name),
             recommendedPackages: 5,
+            distribution: distribution.replace('-', ''),
           },
         });
 
@@ -98,6 +99,7 @@ const PackageRecommendations = () => {
               isPreview: isBeta(),
               shownRecommendations: response.data.packages,
               selectedPackages: packages.map((pkg) => pkg.name),
+              distribution: distribution.replace('-', ''),
             }
           );
         }
@@ -266,6 +268,7 @@ const PackageRecommendations = () => {
                                     (pkg) => pkg.name
                                   ),
                                   shownRecommendations: data.packages,
+                                  distribution: distribution.replace('-', ''),
                                 }
                               );
                               addRecommendedPackage(pkg);