feat: add comprehensive validation framework

Add validators package with 6 specialized validators:
- base.py: Abstract base validator with common patterns
- context_contract.py: PM mode context validation
- dep_sanity.py: Dependency consistency checks
- runtime_policy.py: Runtime policy enforcement
- security_roughcheck.py: Security vulnerability scanning
- test_runner.py: Automated test execution validation

Supports validation gates for quality assurance and risk mitigation.

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

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

superclaude/validators/__init__.py

@@ -0,0 +1,27 @@
+"""Validators for PM Mode
+
+Enforce Context Contract rules before code execution:
+- context_contract: Project-specific rules (Kong, Infisical, etc.)
+- dep_sanity: Dependency existence and version sanity
+- runtime_policy: Runtime (Node/Python) version validation
+- test_runner: Test execution and validation
+- security_roughcheck: Common security anti-patterns
+"""
+
+from .base import ValidationResult, Validator, ValidationStatus
+from .context_contract import ContextContractValidator
+from .dep_sanity import DependencySanityValidator
+from .runtime_policy import RuntimePolicyValidator
+from .test_runner import TestRunnerValidator
+from .security_roughcheck import SecurityRoughcheckValidator
+
+__all__ = [
+    "ValidationResult",
+    "ValidationStatus",
+    "Validator",
+    "ContextContractValidator",
+    "DependencySanityValidator",
+    "RuntimePolicyValidator",
+    "TestRunnerValidator",
+    "SecurityRoughcheckValidator",
+]