feat: add _cnd conditional operator support and n8n 2.0+ executeWorkflowTrigger fix

Added:
- Support for all 12 _cnd operators in displayOptions validation (eq, not, gte, lte, gt, lt, between, startsWith, endsWith, includes, regex, exists)
- Version-based visibility checking with @version in config
- 42 new unit tests for _cnd operators

Fixed:
- n8n 2.0+ breaking change: executeWorkflowTrigger now recognized as activatable trigger
- Removed outdated validation blocking Execute Workflow Trigger workflows

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

dist/services/config-validator.d.ts

@@ -30,7 +30,9 @@ export declare class ConfigValidator {
     }>): ValidationResult[];
     private static checkRequiredProperties;
     private static getPropertyVisibility;
-    protected static isPropertyVisible(prop: any, config: Record<string, any>): boolean;
+    private static evaluateCondition;
+    private static valueMatches;
+    static isPropertyVisible(prop: any, config: Record<string, any>): boolean;
     private static validatePropertyTypes;
     private static performNodeSpecificValidation;
     private static validateHttpRequest;