fix(supply): label framework install version as 'manifest default'

Copilot review: '(default: X)' could read as 'the buildpack installs this by
default'. Say 'manifest default' — for java-cfenv the manifest default differs
from the version actually installed (resolved per Spring Boot major).

Author: stokpop

src/java/supply/supply.go

@@ -181,5 +181,7 @@ func (s *Supplier) frameworkVersionSuffix(framework frameworks.Framework) string
 		return ""
 	}
 
-	return fmt.Sprintf(" (default: %s)", dependency.Version)
+	// "manifest default" — the default version listed in manifest.yml, not necessarily what
+	// gets installed (e.g. java-cfenv resolves to a Spring-Boot-major-specific version).
+	return fmt.Sprintf(" (manifest default: %s)", dependency.Version)
 }