refactor(plugins): simplify linting output to errors only

Streamlined plugin validation to focus on critical issues by showing only errors. Warnings and suggestions are now suppressed for plugins to reduce noise and align with Anthropic's plugin patterns where many suggestions don't apply.

Changes:
- Filter validation issues to show errors only
- Promote secrets detection to errors (critical security issue)
- Skip warnings and suggestions for plugin manifests

Author: garyblankenship

internal/cli/plugins.go

@@ -44,25 +44,24 @@ func LintPlugins(rootPath string, quiet bool, verbose bool) (*LintSummary, error
 			summary.TotalErrors++
 		} else {
 			// Validate plugin-specific rules
+			// NOTE: Only show errors for plugins until we can improve the suggestions
 			allIssues := validatePluginSpecific(data, file.RelPath, file.Contents)
 			for _, issue := range allIssues {
-				switch issue.Severity {
-				case "suggestion":
-					result.Suggestions = append(result.Suggestions, issue)
-					summary.TotalSuggestions++
-				case "warning":
-					result.Warnings = append(result.Warnings, issue)
-					summary.TotalWarnings++
-				default:
+				if issue.Severity == "error" {
 					result.Errors = append(result.Errors, issue)
 					summary.TotalErrors++
 				}
+				// Skip suggestions and warnings for plugins
 			}
 
-			// Secrets detection
+			// Secrets detection - keep as errors only for plugins
 			secretWarnings := detectSecrets(file.Contents, file.RelPath)
-			result.Warnings = append(result.Warnings, secretWarnings...)
-			summary.TotalWarnings += len(secretWarnings)
+			for _, w := range secretWarnings {
+				// Promote secrets to errors since they're important
+				w.Severity = "error"
+				result.Errors = append(result.Errors, w)
+				summary.TotalErrors++
+			}
 
 			if len(result.Errors) == 0 {
 				summary.SuccessfulFiles++