fix(cli): remove stray brace in runPlatformHealth causing syntax error

The yaml-output-support refactor removed the combined json/yaml if-block
but left a dangling `}` that closed runPlatformHealth prematurely,
putting the tabwriter block outside the function body.

Removes the stray brace at line 137. CI vet was failing with:
  platform.go:138:2: syntax error: non-declaration statement outside function body

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/cmd/platform.go

@@ -134,7 +134,6 @@ func runPlatformHealth(cmd *cobra.Command, _ []string) error {
 	if outputFormat == "yaml" {
 		return printYAML(h)
 	}
-	}
 	w := tabwriter.NewWriter(os.Stdout, 0, 4, 2, ' ', 0)
 	kv(w, "Status", h.Status)
 	kv(w, "Version", h.Version)